U.S. patent number 11,022,884 [Application Number 15/325,769] was granted by the patent office on 2021-06-01 for silicon-containing resist underlayer film-forming composition having halogenated sulfonylalkyl group.
This patent grant is currently assigned to NISSAN CHEMICAL INDUSTRIES, LTD.. The grantee listed for this patent is NISSAN CHEMICAL INDUSTRIES, LTD.. Invention is credited to Makoto Nakajima, Rikimaru Sakamoto, Wataru Shibayama, Kenji Takase, Satoshi Takeda, Hiroyuki Wakayama.
View All Diagrams
United States Patent |
11,022,884 |
Shibayama , et al. |
June 1, 2021 |
Silicon-containing resist underlayer film-forming composition
having halogenated sulfonylalkyl group
Abstract
A resist underlayer film allows an excellent resist pattern
shape to be formed when an upper resist layer is exposed to light
and developed using an alkaline developing solution or organic
solvent; and composition for forming the resist underlayer film. A
resist underlayer film-forming composition for lithography, the
composition including, as a silane, hydrolyzable silane, hydrolysis
product thereof, hydrolysis-condensation product thereof, or
combination, wherein the hydrolyzable silane includes hydrolyzable
silane of Formula (1):
R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4-(a+b) Formula (1)
[where R.sup.1 is an organic group of Formula (2):
--R.sup.4--R.sup.5--R.sup.6 Formula (2) (where R4 is optionally
substituted C1-10 alkylene group; R5 is a sulfonyl group or
sulfonamide group; and R6 is a halogen-containing organic group)].
In Formula (2), R6 may be a fluorine-containing organic group like
trifluoromethyl group. A resist underlayer film obtained by
applying the resist underlayer film-forming composition onto a
semiconductor substrate, followed by baking. The underlayer
film-forming composition may include acid as a hydrolysis catalyst,
or water.
Inventors: |
Shibayama; Wataru (Toyama,
JP), Takase; Kenji (Funabashi, JP),
Nakajima; Makoto (Toyama, JP), Takeda; Satoshi
(Toyama, JP), Wakayama; Hiroyuki (Toyama,
JP), Sakamoto; Rikimaru (Toyama, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
NISSAN CHEMICAL INDUSTRIES, LTD. |
Tokyo |
N/A |
JP |
|
|
Assignee: |
NISSAN CHEMICAL INDUSTRIES,
LTD. (Tokyo, JP)
|
Family
ID: |
55078433 |
Appl.
No.: |
15/325,769 |
Filed: |
July 9, 2015 |
PCT
Filed: |
July 09, 2015 |
PCT No.: |
PCT/JP2015/069761 |
371(c)(1),(2),(4) Date: |
January 12, 2017 |
PCT
Pub. No.: |
WO2016/009939 |
PCT
Pub. Date: |
January 21, 2016 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20170168397 A1 |
Jun 15, 2017 |
|
Foreign Application Priority Data
|
|
|
|
|
Jul 15, 2014 [JP] |
|
|
JP2014-145213 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L
21/30604 (20130101); G03F 7/11 (20130101); G03F
7/091 (20130101); H01L 21/3081 (20130101); C08G
77/28 (20130101); G03F 7/327 (20130101); G03F
7/162 (20130101); H01L 21/3086 (20130101); C08G
77/24 (20130101); G03F 7/168 (20130101); G03F
7/2004 (20130101); C09D 183/08 (20130101); G03F
7/0752 (20130101); G03F 7/38 (20130101) |
Current International
Class: |
G03F
7/11 (20060101); C08G 77/24 (20060101); G03F
7/075 (20060101); G03F 7/09 (20060101); C08G
77/28 (20060101); C09D 183/08 (20060101); G03F
7/16 (20060101); G03F 7/20 (20060101); G03F
7/32 (20060101); G03F 7/38 (20060101); H01L
21/306 (20060101); H01L 21/308 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2012-533675 |
|
Dec 2012 |
|
JP |
|
201127880 |
|
Aug 2011 |
|
TW |
|
2011033965 |
|
Mar 2011 |
|
WO |
|
2013022099 |
|
Feb 2013 |
|
WO |
|
2013191203 |
|
Dec 2013 |
|
WO |
|
WO 2014/098076 |
|
Jun 2014 |
|
WO |
|
Other References
Sep. 8, 2015 Written Opinion of the International Searching
Authority issued in International Patent Application No.
PCT/JP2015/069761. cited by applicant .
Sep. 8, 2015 Search Report issued in International Application No.
PCT/JP2015/069761. cited by applicant.
|
Primary Examiner: Hamilton; Cynthia
Attorney, Agent or Firm: Oliff PLC
Claims
The invention claimed is:
1. A resist underlayer film-forming composition for lithography,
the composition comprising at least one silane, the at least one
silane comprising: a hydrolyzable silane, a hydrolysis product
thereof, a hydrolysis-condensation product thereof, or a
combination of these, in which the hydrolyzable silane comprises a
hydrolyzable silane of Formula (1):
R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4-(a+b) Formula (1) where
R.sup.1 is an organic group of Formula (2):
--R.sup.4--R.sup.5--R.sup.6 Formula (2) where R.sup.4 is an
optionally substituted C.sub.1-10 alkylene group, R.sup.5 is a
sulfonyl group, and R.sup.6 is a perfluoromethyl group, a
perfluoroethyl group, a perfluoropropyl group, or a perfluorobutyl
group, and is bonded to a silicon atom through a Si--C bond;
R.sup.2 is an alkyl group, an aryl group, a halogenated alkyl
group, a halogenated aryl group, an alkoxyaryl group, an alkenyl
group, or an organic group having an epoxy group, an acryloyl
group, a methacryloyl group, a mercapto group, an amino group, or a
cyano group, and is bonded to a silicon atom through a Si--C bond;
R.sup.3 is an alkoxy group, an acyloxy group, or a halogen group; a
is an integer of 1; b is an integer of 0 to 2; and a+b is an
integer of 1 to 3; wherein in terms of the total moles of the at
least one silane, the hydrolyzable silane of Formula (1) is present
in an amount in the range of from 0.1% by mole to 10% by mole.
2. The resist underlayer film-forming composition according to
claim 1, wherein in Formula (2), R.sup.6 is a perfluorobutyl
group.
3. The resist underlayer film-forming composition according to
claim 1, wherein in Formula (2), R.sup.6 is a trifluoromethyl
group.
4. The resist underlayer film-forming composition according to
claim 1, wherein the hydrolyzable silane is a combination of the
hydrolyzable silane of Formula (1) and another hydrolyzable silane,
the other hydrolyzable silane being at least one hydrolyzable
silane selected from the group consisting of a hydrolyzable silane
of Formula (3): R.sup.7.sub.cSi(R.sup.8).sub.4-c Formula (3) where
R.sup.7 is an alkyl group, an aryl group, a halogenated alkyl
group, a halogenated aryl group, an alkoxyaryl group, an alkenyl
group, or an organic group having an epoxy group, an acryloyl
group, a methacryloyl group, a mercapto group, or a cyano group,
and is bonded to a silicon atom through a Si--C bond; R.sup.8 is an
alkoxy group, an acyloxy group, or a halogen group; and c is an
integer of 0 to 3; and a hydrolyzable silane of Formula (4):
[R.sup.9.sub.dSi(R.sup.10).sub.3-d].sub.2Y.sub.e Formula (4) where
R.sup.9 is an alkyl group and is bonded to a silicon atom through a
Si--C bond; R.sup.10 is an alkoxy group, an acyloxy group, or a
halogen group; Y is an alkylene group or an arylene group; d is an
integer of 0 or 1; and e is an integer of 0 or 1.
5. The resist underlayer film-forming composition according to
claim 1, further comprising an acid as a hydrolysis catalyst.
6. The resist underlayer film-forming composition according to
claim 1, further comprising water.
7. A resist underlayer film obtained by applying the resist
underlayer film-forming composition as claimed in claim 1 onto a
semiconductor substrate, followed by baking.
8. A method for manufacturing a semiconductor device, the method
comprising the steps of: applying the resist underlayer
film-forming composition as claimed in claim 1 onto a semiconductor
substrate, followed by baking to form a resist underlayer film;
applying a resist composition onto the underlayer film to form a
resist film; exposing the resist film to light; developing the
resist film after the light exposure to obtain a resist pattern;
etching the resist underlayer film with the resist pattern; and
processing the semiconductor substrate with the patterned resist
underlayer film.
9. A method for manufacturing a semiconductor device, the method
comprising the steps of: forming an organic underlayer film on a
semiconductor substrate; applying the resist underlayer
film-forming composition as claimed in claim 1 onto the organic
underlayer film, followed by baking to form a resist underlayer
film; applying a resist composition onto the resist underlayer film
to form a resist film; exposing the resist film to light;
developing the resist film after the light exposure to obtain a
resist pattern; etching the resist underlayer film with the resist
pattern; etching the organic underlayer film with the patterned
resist underlayer film; and processing the semiconductor substrate
with the patterned organic underlayer film.
10. The resist underlayer film-forming composition according to
claim 1, wherein b is an integer of 1 or 2; and R.sup.2 is an aryl
group, a halogenated aryl group, or an alkoxyaryl group, and the
organic group is bonded to the silicon atom through a Si--C
bond.
11. The resist underlayer film-forming composition according to
claim 1, wherein b is an integer of 1 or 2; and R.sup.2 is an
organic group having an epoxy group, an acryloyl group, a
methacryloyl group, a mercapto group, an amino group, or a cyano
group, and the organic group is bonded to the silicon atom through
a Si--C bond.
12. The resist underlayer film-forming composition according to
claim 11, wherein the organic group selected from the group
consisting of glycidoxymethyl, glycidoxyethyl, glycidoxypropyl,
glycidoxybutyl, and epoxycyclohexyl.
13. The resist underlayer film-forming composition according to
claim 11, wherein the organic group is selected from the group
consisting of acryloylmethyl, acryloylethyl, and
acryloylpropyl.
14. The resist underlayer film-forming composition according to
claim 11, wherein the organic group is selected from the group
consisting of methacryloylmethyl, methacryloylethyl, and
methacryloylpropyl.
15. The resist underlayer film-forming composition according to
claim 11, wherein the organic group is selected from the group
consisting of ethylmercapto, butylmercapto, hexylmercapto, and
octylmercapto.
16. The resist underlayer film-forming composition according to
claim 11, wherein the organic group is selected from the group
consisting of aminomethyl, aminoethyl, and aminopropyl.
17. The resist underlayer film-forming composition according to
claim 11, wherein the organic group is selected from the group
consisting of cyanoethyl and cyanopropyl.
18. A resist underlayer film-forming composition, comprising, as an
underlayer film-forming polymer, a hydrolysis-condensation product
of a hydrolyzable silane comprising a combination of 0.1% by mole
to 10% by mole of a hydrolyzable silane of Formula (1):
R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4-(a+b) Formula (1) where
R.sup.1 is an organic group of Formula (2):
--R.sup.4--R.sup.5--R.sup.6 Formula (2) where R.sup.4 is an
optionally substituted C.sub.1-10 alkylene group, R.sup.5 is a
sulfonyl group, and R.sup.6 is a perfluoromethyl group, a
perfluoroethyl group, a perfluoropropyl group, or a perfluorobutyl
group, and is bonded to a silicon atom through a Si--C bond;
R.sup.2 is an alkyl group, an aryl group, a halogenated alkyl
group, a halogenated aryl group, an alkoxyaryl group, an alkenyl
group, or an organic group having an epoxy group, an acryloyl
group, a methacryloyl group, a mercapto group, an amino group, or a
cyano group, and is bonded to a silicon atom through a Si--C bond;
R.sup.3 is an alkoxy group, an acyloxy group, or a halogen group; a
is an integer of 1; b is an integer of 0 to 2; and a+b is an
integer of 1 to 3; and a hydrolyzable silane of Formula (3):
R.sup.7.sub.cSi(R.sup.8).sub.4-c Formula (3) where R.sup.7 is an
alkyl group, an aryl group, a halogenated alkyl group, a
halogenated aryl group, an alkoxyaryl group, an alkenyl group, or
an organic group having an epoxy group, an acryloyl group, a
methacryloyl group, a mercapto group, or a cyano group, and is
bonded to a silicon atom through a Si--C bond; R.sup.8 is an alkoxy
group, an acyloxy group, or a halogen group; and c is an integer of
0 to 3.
Description
TECHNICAL FIELD
The present invention relates to a composition for forming an
underlayer film between a substrate and a resist (such as a
photoresist or an electron beam resist) for use in the manufacture
of semiconductor devices. Specifically, the present invention
relates to a resist underlayer film-forming composition for
lithography for forming an underlayer film used as a layer under a
photoresist in a lithography process for the manufacture of
semiconductor devices. Furthermore, the present invention relates
to a method for forming a resist pattern using the underlayer
film-forming composition.
BACKGROUND ART
In the manufacture of semiconductor devices, fine processing by
lithography using photoresists has been conventionally performed.
The fine processing is a processing method including: forming a
photoresist thin film on a semiconductor substrate such as a
silicon wafer; irradiating the thin film with an active ray such as
ultraviolet ray through a mask pattern having a semiconductor
device pattern depicted therein; carrying out development; and
etching the substrate with the obtained photoresist pattern as a
protective film, thereby forming fine projections and depressions
corresponding to the pattern, on the surface of the substrate.
However, with the higher integration of semiconductor devices in
recent years, an active ray to be used tends to have a shorter
wavelength, namely, shift from KrF excimer laser (248 nm) to ArF
excimer laser (193 nm). Accordingly, the influence of reflection of
the active ray on a semiconductor substrate has become a serious
problem.
A film known as a hard mask containing metal elements, such as
silicon and titanium, has been used as an underlayer film between a
semiconductor substrate and a photoresist. In this case, the
photoresist and the hard mask are significantly different in
components, and the rates to remove these by dry etching are
greatly dependent on the types of gas used for dry etching.
Therefore, the appropriate selection of a gas type allows the hard
mask to be removed by dry etching without a large reduction in the
film thickness of the photoresist. Thus, in the manufacture of
semiconductor devices in recent years, a resist underlayer film has
been increasingly disposed between a semiconductor substrate and a
photoresist to achieve various effects such as an anti-reflection
effect. Compositions for photoresist underlayer films have been
studied, but, because of the diversity of characteristics demanded
of the compositions, development of novel materials for photoresist
underlayer films has been desired.
For example, a resist underlayer film comprising a polysiloxane
including a silane having a sulfone structure has been proposed
(refer to Patent Document 1).
A resist underlayer film comprising a polysiloxane including a
silane having a sulfonamide structure has been proposed (refer to
Patent Document 2).
A resist underlayer film comprising a polysiloxane including a
silane having a sulfone structure and an amine structure has been
proposed (refer to Patent Document 3).
PRIOR ART DOCUMENTS
Patent Documents
Patent Document 1: WO 2013/022099
Patent Document 2: WO 2011/033965
Patent Document 3: WO 2013/191203
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
It is an object of the present invention to provide a resist
underlayer film-forming composition for lithography for use in the
manufacture of semiconductor devices. Specifically, it is an object
of the present invention to provide a resist underlayer
film-forming composition for lithography for forming a resist
underlayer film that can be used as a hard mask. Furthermore, it is
an object of the present invention to provide a resist underlayer
film-forming composition for lithography for forming a resist
underlayer film that can be used as an anti-reflective coating.
Furthermore, it is an object of the present invention to provide a
resist underlayer film for lithography, in which the resist
underlayer film does not intermix with a resist and a dry etching
rate of the resist underlayer film can be made higher than that of
the resist, and to provide a resist underlayer film-forming
composition for forming the underlayer film.
In particular, it is an object of the present invention to provide
a resist underlayer film-forming composition for forming a resist
underlayer film that allows an excellent resist pattern shape to be
formed when a resist as an upper layer is exposed to light and
developed using an alkaline developing solution or an organic
solvent, and that allows a rectangular resist pattern to be
transferred to an underlayer by subsequent dry etching.
Means for Solving the Problem
The present invention provides:
according to a first aspect, a resist underlayer film-forming
composition for lithography, the composition comprising, as a
silane, a hydrolyzable silane, a hydrolysis product thereof, a
hydrolysis-condensation product thereof, or a combination of these,
in which the hydrolyzable silane comprises a hydrolyzable silane of
Formula (1): R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4-(a+b)
Formula (1) [where R.sup.1 is an organic group of Formula (2):
--R.sup.4--R.sup.5--R.sup.6 Formula (2) (where R.sup.4 is an
optionally substituted C.sub.1-10 alkylene group; R.sup.5 is a
sulfonyl group or a sulfonamide group; and R.sup.6 is a
halogen-containing organic group), and is bonded to a silicon atom
through a Si--C bond; R.sup.2 is an alkyl group, an aryl group, a
halogenated alkyl group, a halogenated aryl group, an alkoxyaryl
group, an alkenyl group, or an organic group having an epoxy group,
an acryloyl group, a methacryloyl group, a mercapto group, an amino
group, or a cyano group, and is bonded to a silicon atom through a
Si--C bond; R.sup.3 is an alkoxy group, an acyloxy group, or a
halogen group; a is an integer of 1; b is an integer of 0 to 2; and
a+b is an integer of 1 to 3];
according to a second aspect, the resist underlayer film-forming
composition according to the first aspect, in which, in Formula
(2), R.sup.6 is a fluorine-containing organic group;
according to a third aspect, the resist underlayer film-forming
composition according to the first aspect, in which, in Formula
(2), R.sup.6 is a trifluoromethyl group;
according to a fourth aspect, the resist underlayer film-forming
composition according to the first aspect or the second aspect, in
which, the hydrolyzable silane is a combination of the hydrolyzable
silane of Formula (1) and another hydrolyzable silane, the other
hydrolyzable silane being at least one hydrolyzable silane selected
from the group consisting of a hydrolyzable silane of Formula (3):
R.sup.7.sub.cSi(R.sup.8).sub.4-c Formula (3) (where R.sup.7 is an
alkyl group, an aryl group, a halogenated alkyl group, a
halogenated aryl group, an alkoxyaryl group, an alkenyl group, or
an organic group having an epoxy group, an acryloyl group, a
methacryloyl group, a mercapto group, or a cyano group, and is
bonded to a silicon atom through a Si--C bond; R.sup.8 is an alkoxy
group, an acyloxy group, or a halogen group; and c is an integer of
0 to 3), and a hydrolyzable silane of Formula (4):
[R.sup.9.sub.dSi(R.sup.10).sub.3-d].sub.2Y.sub.e Formula (4) (where
R.sup.9 is an alkyl group and is bonded to a silicon atom through a
Si--C bond; R.sup.10 is an alkoxy group, an acyloxy group, or a
halogen group; Y is an alkylene group or an arylene group; d is an
integer of 0 or 1; and e is an integer of 0 or 1);
according to a fifth aspect, a resist underlayer film-forming
composition, comprising, as an underlayer film-forming polymer, a
hydrolysis-condensation product of a hydrolyzable silane comprising
a combination of the hydrolyzable silane of Formula (1) according
to the first aspect and the hydrolyzable silane of Formula (3)
according to the fourth aspect;
according to a sixth aspect, the resist underlayer film-forming
composition according to any one of the first aspect to the fifth
aspect, further comprising an acid as a hydrolysis catalyst;
according to a seventh aspect, the resist underlayer film-forming
composition according to any one of the first aspect to the sixth
aspect, further comprising water;
according to an eighth aspect, a resist underlayer film obtained by
applying the resist underlayer film-forming composition according
to any one of the first aspect to the seventh aspect onto a
semiconductor substrate, followed by baking;
according to a ninth aspect, a method for manufacturing a
semiconductor device, the method comprising the steps of: applying
the resist underlayer film-forming composition according to any one
of the first aspect to the seventh aspect onto a semiconductor
substrate, followed by baking to form a resist underlayer film;
applying a resist composition onto the underlayer film to form a
resist film; exposing the resist film to light; developing the
resist film after the light exposure to obtain a resist pattern;
etching the resist underlayer film with the resist pattern; and
processing the semiconductor substrate with the patterned resist
underlayer film; and according to a tenth aspect, a method for
manufacturing a semiconductor device, the method comprising the
steps of: forming an organic underlayer film on a semiconductor
substrate; applying the resist underlayer film-forming composition
according to any one of the first aspect to the seventh aspect onto
the organic underlayer film, followed by baking to form a resist
underlayer film; applying a resist composition onto the resist
underlayer film to form a resist film; exposing the resist film to
light; developing the resist film after the light exposure to
obtain a resist pattern; etching the resist underlayer film with
the resist pattern; etching the organic underlayer film with the
patterned resist underlayer film; and processing the semiconductor
substrate with the patterned organic underlayer film.
Effects of the Invention
The resist underlayer film-forming composition of the present
invention can be used for the manufacture of semiconductor devices
by lithography, and can function as a hard mask. This composition
comprises, in a skeleton thereof, a hydrolyzable silane having
sulfonyl or sulfonamide, and a halogen-containing organic group,
and an underlayer film formed from the composition generates an
acid by the irradiation of lasers with various wavelengths and
electron beams, such as KrF, ArF, EUV, and EB. Accordingly, the
composition is useful because the adjustment of the acidity of this
underlayer film allows a resist shape to be controlled, so that the
contrast of a photoresist can be made higher. In particular, in the
case where the composition comprises a hydrolyzable silane having a
trifluoromethanesulfone skeleton, an acid and a base can be
characteristically generated particularly in EUV exposure, whereby
pattern resolution can be improved.
Therefore, when the composition of the present invention is applied
onto a semiconductor substrate or onto an organic underlayer film
on the substrate, a resist underlayer film can be provided in which
the resist underlayer film allows an excellent resist pattern shape
to be formed by light-exposing a resist film, that is, an upper
layer of the resist underlayer film, and developing the resist film
by an alkaline developing solution or an organic solvent, and
allows a rectangular resist pattern to be transferred to the
underlayer of the resist film by subsequent dry etching.
Furthermore, the resist underlayer film formed from the resist
underlayer film-forming composition of the present invention can be
used as an anti-reflective coating, and does not intermix with a
resist and has a dry etching rate higher than that of the
resist.
Therefore, the resist underlayer film-forming composition of the
present invention can be used as, for example, resist underlayer
film-forming compositions for ArF and KrF photoresists; resist
underlayer film-forming compositions for EUV resists; EUV resist
upperlayer film-forming compositions, resist underlayer
film-forming compositions for electron beam resists; electron beam
resist upperlayer film-forming compositions; and reverse
material-forming compositions.
MODES FOR CARRYING OUT THE INVENTION
The present invention provides a resist underlayer film-forming
composition for lithography, the composition comprising, as a
silane, a hydrolyzable silane, a hydrolysis product thereof, a
hydrolysis-condensation product thereof, or a combination of these,
in which the hydrolyzable silane comprises a hydrolyzable silane of
Formula (1).
In Formula (1), R.sup.1 is an organic group of Formula (2) and
bonded to a silicon atom through a Si--C bond. R.sup.2 is an alkyl
group, an aryl group, a halogenated alkyl group, a halogenated aryl
group, an alkoxyaryl group, an alkenyl group, or an organic group
having an epoxy group, an acryloyl group, a methacryloyl group, a
mercapto group, an amino group, or a cyano group, and is bonded to
a silicon atom through a Si--C bond. R.sup.3 is an alkoxy group, an
acyloxy group, or a halogen group. a is an integer of 1, b is an
integer of 0 to 2, and a+b is an integer of 1 to 3.
In Formula (2), R.sup.4 is an optionally substituted C.sub.1-10
alkylene group, R.sup.5 is a sulfonyl group or a sulfonamide group,
and R.sup.6 is a halogen-containing organic group.
R.sup.6 in Formula (2) above is preferably a fluorine-containing
organic group, and particularly preferably a trifluoromethyl
group.
In the whole of the silane, the silane of Formula (1) may be used
in a range of 50% by mole or less, 0.05% by mole to 50% by mole,
0.1% by mole to 30% by mole, or 0.1% by mole to 10% by mole.
The resist underlayer film-forming composition of the present
invention comprises: the hydrolyzable silane of Formula (1), or the
hydrolyzable silane of Formula (1) and another hydrolyzable silane
(for example, a hydrolyzable silane of Formula (3)), a hydrolysis
product thereof, or a hydrolysis-condensation product thereof, and
a solvent. The resist underlayer film-forming composition may
further comprise, as optional components, an acid, water, alcohol,
a curing catalyst, an acid generator, other organic polymers, a
light-absorbing compound, and a surfactant.
The resist underlayer film-forming composition of the present
invention has a solid content of, for example, 0.1% by mass to 50%
by mass, 0.1% by mass to 30% by mass, or 0.1% by mass to 25% by
mass. Here, the solid content is a content obtained by subtracting
solvent components from all components of the resist underlayer
film-forming composition.
The proportion of the hydrolyzable silane, the hydrolysis product
thereof, and the hydrolysis-condensation product thereof in the
solid content is 20% by mass or more, for example, 50% by mass to
100% by mass, 60% by mass to 99% by mass, or 70% by mass to 99% by
mass.
Furthermore, the above-mentioned hydrolyzable silane, the
hydrolysis product thereof, and the hydrolysis-condensation product
thereof may be used in the form of a mixture thereof. A
condensation product obtained by hydrolyzing the hydrolyzable
silane and condensing the resulting hydrolysis product may be used.
Furthermore, a mixture may be used, obtained by mixing a
hydrolysis-condensation product with a silane compound and a
partial-hydrolysis product in which the hydrolysis to obtain the
hydrolysis-condensation product has not been perfectly completed.
Such condensation product is a polymer having a polysiloxane
structure. This polysiloxane includes a hydrolysis-condensation
product of the hydrolyzable silane of Formula (1), or the
hydrolyzable silane of Formula (1) and another hydrolyzable silane
(for example, the hydrolyzable silane of Formula (3)). Furthermore,
the hydrolyzable silane of Formula (1), or a hydrolyzable silane
formed of the combination of the hydrolyzable silane of Formula (1)
and the hydrolyzable silane of Formula (3) may be added to a
hydrolysis-condensation product (polysiloxane) of a hydrolysis
product of the hydrolyzable silane of Formula (1) or a hydrolyzable
silane formed of a combination of the hydrolyzable silane of
Formula (1) and the hydrolyzable silane of Formula (3).
The above-mentioned alkyl group is a linear or branched C.sub.1-10
alkyl group, and examples of the alkyl group include methyl group,
ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl
group, s-butyl group, t-butyl group, n-pentyl group,
1-methyl-n-butyl group, 2-methyl-n-butyl group, 3-methyl-n-butyl
group, 1,1-dimethyl-n-propyl group, 1,2-dimethyl-n-propyl group,
2,2-dimethyl-n-propyl group, 1-ethyl-n-propyl group, n-hexyl group,
1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl
group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group,
1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group,
2,2-dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group,
3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl
group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl
group, 1-ethyl-1-methyl-n-propyl group, and
1-ethyl-2-methyl-n-propyl group.
Furthermore, a cyclic alkyl group may be used, and examples of a
cyclic C.sub.1-10 alkyl group include cyclopropyl group, cyclobutyl
group, 1-methyl-cyclopropyl group, 2-methyl-cyclopropyl group,
cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl
group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group,
2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group,
2-ethyl-cyclopropyl group, cyclohexyl group, 1-methyl-cyclopentyl
group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group,
1-ethyl-cyclobutyl group, 2-ethyl-cyclobutyl group,
3-ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group,
1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group,
2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group,
3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group,
2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group,
2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group,
1,2,3-trimethyl-cyclopropyl group, 2,2,3-trimethyl-cyclopropyl
group, 1-ethyl-2-methyl-cyclopropyl group,
2-ethyl-1-methyl-cyclopropyl group, 2-ethyl-2-methyl-cyclopropyl
group, and 2-ethyl-3-methyl-cyclopropyl group. These examples are
also applied to an alkyl group portion of the above-mentioned
halogenated alkyl group.
The above-mentioned alkylene group may be, for example, alkylene
groups derived from the above-mentioned alkyl groups. Examples of
such alkylene groups include methylene group derived from methyl
group, ethylene group derived from ethyl group, and propylene group
derived from propyl group.
The above-mentioned alkenyl group is a C.sub.2-10 alkenyl group,
and examples of such alkenyl group include ethenyl group,
1-propenyl group, 2-propenyl group, 1-methyl-1-ethenyl group,
1-butenyl group, 2-butenyl group, 3-butenyl group,
2-methyl-1-propenyl group, 2-methyl-2-propenyl group,
1-ethylethenyl group, 1-methyl-1-propenyl group,
1-methyl-2-propenyl group, 1-pentenyl group, 2-pentenyl group,
3-pentenyl group, 4-pentenyl group, 1-n-propylethenyl group,
1-methyl-1-butenyl group, 1-methyl-2-butenyl group,
1-methyl-3-butenyl group, 2-ethyl-2-propenyl group,
2-methyl-1-butenyl group, 2-methyl-2-butenyl group,
2-methyl-3-butenyl group, 3-methyl-1-butenyl group,
3-methyl-2-butenyl group, 3-methyl-3-butenyl group,
1,1-dimethyl-2-propenyl group, 1-i-propylethenyl group,
1,2-dimethyl-1-propenyl group, 1,2-dimethyl-2-propenyl group,
1-cyclopentenyl group, 2-cyclopentenyl group, 3-cyclopentenyl
group, 1-hexenyl group, 2-hexenyl group, 3-hexenyl group, 4-hexenyl
group, 5-hexenyl group, 1-methyl-1-pentenyl group,
1-methyl-2-pentenyl group, 1-methyl-3-pentenyl group,
1-methyl-4-pentenyl group, 1-n-butylethenyl group,
2-methyl-1-pentenyl group, 2-methyl-2-pentenyl group,
2-methyl-3-pentenyl group, 2-methyl-4-pentenyl group,
2-n-propyl-2-propenyl group, 3-methyl-1-pentenyl group,
3-methyl-2-pentenyl group, 3-methyl-3-pentenyl group,
3-methyl-4-pentenyl group, 3-ethyl-3-butenyl group,
4-methyl-1-pentenyl group, 4-methyl-2-pentenyl group,
4-methyl-3-pentenyl group, 4-methyl-4-pentenyl group,
1,1-dimethyl-2-butenyl group, 1,1-dimethyl-3-butenyl group,
1,2-dimethyl-1-butenyl group, 1,2-dimethyl-2-butenyl group,
1,2-dimethyl-3-butenyl group, 1-methyl-2-ethyl-2-propenyl group,
1-s-butylethenyl group, 1,3-dimethyl-1-butenyl group,
1,3-dimethyl-2-butenyl group, 1,3-dimethyl-3-butenyl group,
1-i-butylethenyl group, 2,2-dimethyl-3-butenyl group,
2,3-dimethyl-1-butenyl group, 2,3-dimethyl-2-butenyl group,
2,3-dimethyl-3-butenyl group, 2-i-propyl-2-propenyl group,
3,3-dimethyl-1-butenyl group, 1-ethyl-1-butenyl group,
1-ethyl-2-butenyl group, 1-ethyl-3-butenyl group,
1-n-propyl-1-propenyl group, 1-n-propyl-2-propenyl group,
2-ethyl-1-butenyl group, 2-ethyl-2-butenyl group, 2-ethyl-3-butenyl
group, 1,1,2-trimethyl-2-propenyl group, 1-t-butylethenyl group,
1-methyl-1-ethyl-2-propenyl group, 1-ethyl-2-methyl-1-propenyl
group, 1-ethyl-2-methyl-2-propenyl group, 1-i-propyl-1-propenyl
group, 1-i-propyl-2-propenyl group, 1-methyl-2-cyclopentenyl group,
1-methyl-3-cyclopentenyl group, 2-methyl-1-cyclopentenyl group,
2-methyl-2-cyclopentenyl group, 2-methyl-3-cyclopentenyl group,
2-methyl-4-cyclopentenyl group, 2-methyl-5-cyclopentenyl group,
2-methylene-cyclopentyl group, 3-methyl-1-cyclopentenyl group,
3-methyl-2-cyclopentenyl group, 3-methyl-3-cyclopentenyl group,
3-methyl-4-cyclopentenyl group, 3-methyl-5-cyclopentenyl group,
3-methylene-cyclopentyl group, 1-cyclohexenyl group, 2-cyclohexenyl
group, and 3-cyclohexenyl group.
The above-mentioned aryl group is, for example, a C.sub.6-20 aryl
group, and examples of such aryl groups include phenyl group,
o-methylphenyl group, m-methylphenyl group, p-methylphenyl group,
o-chlorophenyl group, m-chlorophenyl group, p-chlorophenyl group,
o-fluorophenyl group, p-mercaptophenyl group, o-methoxyphenyl
group, p-methoxyphenyl group, p-aminophenyl group, p-cyanophenyl
group, .alpha.-naphthyl group, .beta.-naphthyl group, o-biphenylyl
group, m-biphenylyl group, p-biphenylyl group, 1-anthryl group,
2-anthryl group, 9-anthryl group, 1-phenanthryl group,
2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, and
9-phenanthryl group. These examples are also applied to aryl group
portions of the above-mentioned halogenated aryl group and the
above-mentioned alkoxyaryl group.
Furthermore, examples of the above-mentioned arylene group include
divalent organic groups derived from the above-mentioned aryl
groups.
Examples of the above-mentioned organic group having an epoxy group
include glycidoxymethyl, glycidoxyethyl, glycidoxypropyl,
glycidoxybutyl, and epoxycyclohexyl.
Examples of the above-mentioned organic group having an acryloyl
group include acryloylmethyl, acryloylethyl, and
acryloylpropyl.
Examples of the above-mentioned organic group having a methacryloyl
group include methacryloylmethyl, methacryloylethyl, and
methacryloylpropyl.
Examples of the above-mentioned organic group having a mercapto
group include ethylmercapto, butylmercapto, hexylmercapto, and
octylmercapto.
Examples of the above-mentioned organic group having an amino group
include aminomethyl, aminoethyl, and aminopropyl.
Examples of the above-mentioned organic group having a cyano group
include cyanoethyl and cyanopropyl.
The above-mentioned alkoxy group is, for example, an alkoxy group
having a linear, branched, or cyclic C.sub.1-20 alkyl portion.
Examples of such alkoxy groups include methoxy group, ethoxy group,
n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group,
s-butoxy group, t-butoxy group, n-pentyloxy group,
1-methyl-n-butoxy group, 2-methyl-n-butoxy group, 3-methyl-n-butoxy
group, 1,1-dimethyl-n-propoxy group, 1,2-dimethyl-n-propoxy group,
2,2-dimethyl-n-propoxy group, 1-ethyl-n-propoxy group, n-hexyloxy
group, 1-methyl-n-pentyloxy group, 2-methyl-n-pentyloxy group,
3-methyl-n-pentyloxy group, 4-methyl-n-pentyloxy group,
1,1-dimethyl-n-butoxy group, 1,2-dimethyl-n-butoxy group,
1,3-dimethyl-n-butoxy group, 2,2-dimethyl-n-butoxy group,
2,3-dimethyl-n-butoxy group, 3,3-dimethyl-n-butoxy group,
1-ethyl-n-butoxy group, 2-ethyl-n-butoxy group,
1,1,2-trimethyl-n-propoxy group, 1,2,2-trimethyl-n-propoxy group,
1-ethyl-1-methyl-n-propoxy group, and 1-ethyl-2-methyl-n-propoxy
group; and examples of the cyclic alkoxy group include cyclopropoxy
group, cyclobutoxy group, 1-methyl-cyclopropoxy group,
2-methyl-cyclopropoxy group, cyclopentyloxy group,
1-methyl-cyclobutoxy group, 2-methyl-cyclobutoxy group,
3-methyl-cyclobutoxy group, 1,2-dimethyl-cyclopropoxy group,
2,3-dimethyl-cyclopropoxy group, 1-ethyl-cyclopropoxy group,
2-ethyl-cyclopropoxy group, cyclohexyloxy group,
1-methyl-cyclopentyloxy group, 2-methyl-cyclopentyloxy group,
3-methyl-cyclopentyloxy group, 1-ethyl-cyclobutoxy group,
2-ethyl-cyclobutoxy group, 3-ethyl-cyclobutoxy group,
1,2-dimethyl-cyclobutoxy group, 1,3-dimethyl-cyclobutoxy group,
2,2-dimethyl-cyclobutoxy group, 2,3-dimethyl-cyclobutoxy group,
2,4-dimethyl-cyclobutoxy group, 3,3-dimethyl-cyclobutoxy group,
1-n-propyl-cyclopropoxy group, 2-n-propyl-cyclopropoxy group,
1-i-propyl-cyclopropoxy group, 2-i-propyl-cyclopropoxy group,
1,2,2-trimethyl-cyclopropoxy group, 1,2,3-trimethyl-cyclopropoxy
group, 2,2,3-trimethyl-cyclopropoxy group,
1-ethyl-2-methyl-cyclopropoxy group, 2-ethyl-1-methyl-cyclopropoxy
group, 2-ethyl-2-methyl-cyclopropoxy group, and
2-ethyl-3-methyl-cyclopropoxy group. These examples are also
applied to an alkoxy group portion of the above-mentioned
alkoxyaryl group.
Examples of the above-mentioned C.sub.2-20 acyloxy group include
methylcarbonyloxy group, ethylcarbonyloxy group,
n-propylcarbonyloxy group, i-propylcarbonyloxy group,
n-butylcarbonyloxy group, i-butylcarbonyloxy group,
s-butylcarbonyloxy group, t-butylcarbonyloxy group,
n-pentylcarbonyloxy group, 1-methyl-n-butylcarbonyloxy group,
2-methyl-n-butylcarbonyloxy group, 3-methyl-n-butylcarbonyloxy
group, 1,1-dimethyl-n-propylcarbonyloxy group,
1,2-dimethyl-n-propylcarbonyloxy group,
2,2-dimethyl-n-propylcarbonyloxy group, 1-ethyl-n-propylcarbonyloxy
group, n-hexylcarbonyloxy group, 1-methyl-n-pentylcarbonyloxy
group, 2-methyl-n-pentylcarbonyloxy group,
3-methyl-n-pentylcarbonyloxy group, 4-methyl-n-pentylcarbonyloxy
group, 1,1-dimethyl-n-butylcarbonyloxy group,
1,2-dimethyl-n-butylcarbonyloxy group,
1,3-dimethyl-n-butylcarbonyloxy group,
2,2-dimethyl-n-butylcarbonyloxy group,
2,3-dimethyl-n-butylcarbonyloxy group,
3,3-dimethyl-n-butylcarbonyloxy group, 1-ethyl-n-butylcarbonyloxy
group, 2-ethyl-n-butylcarbonyloxy group,
1,1,2-trimethyl-n-propylcarbonyloxy group,
1,2,2-trimethyl-n-propylcarbonyloxy group,
1-ethyl-1-methyl-n-propylcarbonyloxy group,
1-ethyl-2-methyl-n-propylcarbonyloxy group, phenylcarbonyloxy
group, and tosylcarbonyloxy group.
Examples of the above-mentioned halogen group and a halogen group
portion of the above-mentioned halogenated alkyl group or the
halogenated aryl group include fluorine, chlorine, bromine, and
iodine.
Examples of the halogen of the above-mentioned halogen-containing
organic group include fluorine, chlorine, bromine, and iodine.
As the halogen-containing organic group, a halogen-containing
organic group that is bonded to a sulfone or sulfonamide group, and
a halogen-containing organic group that forms a salt structure may
be used.
Furthermore, examples of the halogen-containing organic group
include an alkyl group substituted with a halogen atom, and an
organic group including an alkyl group substituted with a halogen
atom. Examples of the alkyl group substituted with a halogen atom
include perfluoromethyl group (that is, trifluoromethyl group),
perfluoroethyl group, perfluoropropyl group, and perfluorobutyl
group.
Examples of the hydrolyzable silane of Formula (1) are as
follows.
##STR00001## ##STR00002## ##STR00003##
In the formulae above, T is a C.sub.1-10 alkyl group, such as
methyl group or ethyl group.
In the present invention, the hydrolyzable silane may be a
combination of the hydrolyzable silane of Formula (1) and another
hydrolyzable silane, in which the other hydrolyzable silane is at
least one hydrolyzable silane selected from the group consisting of
hydrolyzable silanes of Formula (3) and Formula (4).
R.sup.7.sub.cSi(R.sup.8).sub.4-c Formula (3)
In Formula (3), R.sup.7 is an alkyl group, an aryl group, a
halogenated alkyl group, a halogenated aryl group, an alkoxyaryl
group, an alkenyl group, or an organic group having an epoxy group,
an acryloyl group, a methacryloyl group, a mercapto group, or a
cyano group, and is bonded to a silicon atom through a Si--C bond;
R.sup.8 is an alkoxy group, an acyloxy group, or a halogen group;
and c is an integer of 0 to 3.
[R.sup.9.sub.dSi(R.sup.10).sub.3-d].sub.2Y.sub.e Formula (4)
In Formula (4), R.sup.9 is an alkyl group and is bonded to a
silicon atom through a Si--C bond; R.sup.10 is an alkoxy group, an
acyloxy group, or a halogen group; Y is an alkylene group or an
arylene group; d is an integer of 0 or 1; and e is an integer of 0
or 1.
As the above-mentioned alkyl group, the aryl group, the halogenated
alkyl group, the halogenated aryl group, the alkenyl group, the
organic group having an epoxy group, an acryloyl group, a
methacryloyl group, a mercapto group, or a cyano group, the alkoxy
group, the acyloxy group, the halogen group, or the arylene group,
the above-mentioned examples may be used.
Examples of the silicon-containing compound of Formula (3) include
tetramethoxysilane, tetrachlorosilane, tetraacetoxysilane,
tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane,
tetra-n-butoxysilane, methyltrimethoxysilane,
methyltrichlorosilane, methyltriacetoxysilane,
methyltripropoxysilane, methyltributoxysilane,
methyltriamyloxysilane, methyltriphenoxysilane,
methyltribenzyloxysilane, methyltriphenethyloxysilane,
glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane,
.alpha.-glycidoxyethyltrimethoxysilane,
.alpha.-glycidoxyethyltriethoxysilane,
.beta.-glycidoxyethyltrimethoxysilane,
.beta.-glycidoxyethyltriethoxysilane,
.alpha.-glycidoxypropyltrimethoxysilane,
.alpha.-glycidoxypropyltriethoxysilane,
.beta.-glycidoxypropyltrimethoxysilane,
.beta.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropyltrimethoxysilane,
.gamma.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropyltripropoxysilane,
.gamma.-glycidoxypropyltributoxysilane,
.gamma.-glycidoxypropyltriphenoxysilane,
.alpha.-glycidoxybutyltrimethoxysilane,
.alpha.-glycidoxybutyltriethoxysilane,
.beta.-glycidoxybutyltriethoxysilane,
.gamma.-glycidoxybutyltrimethoxysilane,
.gamma.-glycidoxybutyltriethoxysilane,
.delta.-glycidoxybutyltrimethoxysilane,
.delta.-glycidoxybutyltriethoxysilane,
(3,4-epoxycyclohexyl)methyltrimethoxysilane,
(3,4-epoxycyclohexyl)methyltriethoxysilane,
.beta.-(3,4-epoxycyclohexypethyltrimethoxysilane,
.beta.-(3,4-epoxycyclohexypethyltriethoxysilane,
.beta.-(3,4-epoxycyclohexypethyltripropoxysilane,
.beta.-(3,4-epoxycyclohexypethyltributoxysilane,
.beta.-(3,4-epoxycyclohexypethyltriphenoxysilane,
.gamma.-(3,4-epoxycyclohexyl)propyltrimethoxysilane,
.gamma.-(3,4-epoxycyclohexyl)propyltriethoxysilane,
.delta.-(3,4-epoxycyclohexyl)butyltrimethoxysilane,
.delta.-(3,4-epoxycyclohexyl)butyltriethoxysilane,
glycidoxymethylmethyldimethoxysilane,
glycidoxymethylmethyldiethoxysilane,
.alpha.-glycidoxyethylmethyldimethoxysilane,
.alpha.-glycidoxyethylmethyldiethoxysilane,
.beta.-glycidoxyethylmethyldimethoxysilane,
.beta.-glycidoxyethylethyldimethoxysilane,
.alpha.-glycidoxypropylmethyldimethoxysilane,
.alpha.-glycidoxypropylmethyldiethoxysilane,
.beta.-glycidoxypropylmethyldimethoxysilane,
.beta.-glycidoxypropylethyldimethoxysilane,
.gamma.-glycidoxypropylmethyldimethoxysilane,
.gamma.-glycidoxypropylmethyldiethoxysilane,
.gamma.-glycidoxypropylmethyldipropoxysilane,
.gamma.-glycidoxypropylmethyldibutoxysilane,
.gamma.-glycidoxypropylmethyldiphenoxysilane,
.gamma.-glycidoxypropylethyldimethoxysilane,
.gamma.-glycidoxypropylethyldiethoxysilane,
.gamma.-glycidoxypropylvinyldimethoxysilane,
.gamma.-glycidoxypropylvinyldiethoxysilane, ethyltrimethoxysilane,
ethyltriethoxysilane, vinyltrimethoxysilane, vinyltrichlorosilane,
vinyltriacetoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane,
methoxyphenyltrimethoxysilane, methoxyphenyltriethoxysilane,
methoxyphenyltriacetoxysilane, methoxyphenyltrichlorosilane,
methoxybenzyltrimethoxysilane, methoxybenzyltriethoxysilane,
methoxybenzyltriacetoxysi lane, methoxybenzyltrichlorosilane,
methoxyphenethyltrimethoxysilane, methoxyphenethyltriethoxysilane,
methoxyphenethyltriacetoxysilane, methoxyphenethyltrichlorosilane,
ethoxyphenyltrimethoxysilane, ethoxyphenyltriethoxysilane,
ethoxyphenyltriacetoxysilane, ethoxyphenyltrichlorosilane,
ethoxybenzyltrimethoxysilane, ethoxybenzyltriethoxysilane,
ethoxybenzyltriacetoxysilane, ethoxybenzyltrichlorosilane,
isopropoxyphenyltrimethoxysilane, isopropoxyphenyltriethoxysilane,
isopropoxyphenyltriacetoxysilane, isopropoxyphenyltrichlorosilane,
isopropoxybenzyltrimethoxysilane, isopropoxybenzyltriethoxysilane,
isopropoxybenzyltriacetoxysilane, isopropoxybenzyltrichlorosilane,
t-butoxyphenyltrimethoxysilane, t-butoxyphenyltriethoxysilane,
t-butoxyphenyltriacetoxysilane, t-butoxyphenyltrichlorosilane,
t-butoxybenzyltrimethoxysilane, t-butoxybenzyltriethoxysilane,
t-butoxybenzyltriacetoxysilane, t-butoxybenzyltrichlorosilane,
methoxynaphthyltrimethoxysilane, methoxynaphthyltriethoxysilane,
methoxynaphthyltriacetoxysilane, methoxynaphthyltrichlorosilane,
ethoxynaphthyltrimethoxysilane, ethoxynaphthyltriethoxysilane,
ethoxynaphthyltriacetoxysilane, ethoxynaphthyltrichlorosilane,
.gamma.-chloropropyltrimethoxysilane,
.gamma.-chloropropyltriethoxysilane,
.gamma.-chloropropyltriacetoxysilane,
3,3,3-trifluoropropyltrimethoxysilane,
.gamma.-methacryloxypropyltrimethoxysilane,
.gamma.-mercaptopropyltrimethoxysilane,
.gamma.-mercaptopropyltriethoxysilane,
.beta.-cyanoethyltriethoxysilane, chloromethyltrimethoxysilane,
chloromethyltriethoxysilane, dimethyldimethoxysilane,
phenylmethyldimethoxysilane, dimethyldiethoxysilane,
phenylmethyldiethoxysilane,
.gamma.-chloropropylmethyldimethoxysilane,
.gamma.-chloropropylmethyldiethoxysilane, dimethyldiacetoxysilane,
.gamma.-methacryloxypropylmethyldimethoxysilane,
.gamma.-methacryloxypropylmethyldiethoxysilane,
.gamma.-mercaptopropylmethyldimethoxysilane,
.gamma.-mercaptomethyldiethoxysilane, methylvinyldimethoxysilane,
and methylvinyldiethoxysilane.
Furthermore, the following hydrolyzable silanes may be used.
##STR00004## ##STR00005## ##STR00006## ##STR00007## ##STR00008##
##STR00009## ##STR00010## ##STR00011## ##STR00012##
Examples of the silicon-containing compound of Formula (4) include
methylenebistrimethoxysilane, methylenebistrichlorosilane,
methylenebistriacetoxysilane, ethylenebistriethoxysilane,
ethylenebistrichlorosilane, ethylenebistriacetoxysilane,
propylenebistriethoxysilane, butylenebistrimethoxysilane,
phenylenebistrimethoxysilane, phenylenebistriethoxysilane,
phenylenebismethyldiethoxysilane,
phenylenebismethyldimethoxysilane, naphthylenebistrimethoxysilane,
bistrimethoxydisilane, bistriethoxydisilane,
bisethyldiethoxydisilane, and bismethyldimethoxydisilane.
Specific examples of the hydrolysis-condensation product
(polysiloxane) used in the present invention are as follows.
##STR00013## ##STR00014## ##STR00015##
The hydrolysis-condensation product (polyorganosiloxane) of the
hydrolyzable silane has a weight-average molecular weight of 1,000
to 1,000,000, or 1,000 to 100,000. These molecular weights are
obtained by GPC analysis in terms of polystyrene.
The GPC measurement can be performed under conditions, such as the
use of a GPC apparatus (trade name: HLC-8220GPC, manufactured by
Tosoh Corporation), GPC columns (trade name: Shodex KF803L, KF802,
and KF801, manufactured by Showa Denko K.K.), a column temperature
of 40.degree. C., tetrahydrofuran as an eluent (elution solvent), a
flow amount (flow rate) of 1.0 ml/min, and a polystyrene
(manufactured by Showa Denko K.K.) as a standard sample.
For the hydrolysis of an alkoxysilyl group, an acyloxysilyl group,
or a halogenated silyl group, 0.5 mol to 100 mol, preferably 1 mol
to 10 mol of water is used per mol of a hydrolysable group.
Furthermore, 0.001 mol to 10 mol, preferably 0.001 mol to 1 mol of
a hydrolysis catalyst may be used per mol of a hydrolysable
group.
The reaction temperature for hydrolysis and condensation is
normally 20.degree. C. to 80.degree. C.
The hydrolysis may be either completely or partially performed. In
other words, a hydrolysis product and a monomer may remain in a
hydrolysis-condensation product.
A catalyst may be used for the hydrolysis and condensation.
Examples of the hydrolysis catalyst include metal chelate
compounds, organic acids, inorganic acids, organic bases, and
inorganic bases.
Examples of the metal chelate compounds serving as hydrolysis
catalysts include: titanium chelate compounds, such as triethoxy
mono(acetylacetonato)titanium, tri-n-propoxy
mono(acetylacetonato)titanium, tri-i-propoxy
mono(acetylacetonato)titanium, tri-n-butoxy
mono(acetylacetonato)titanium, tri-sec-butoxy
mono(acetylacetonato)titanium, tri-t-butoxy
mono(acetylacetonato)titanium, diethoxy
bis(acetylacetonato)titanium, di-n-propoxy
bis(acetylacetonato)titanium, di-i-propoxy
bis(acetylacetonato)titanium, di-n-butoxy
bis(acetylacetonato)titanium, di-sec-butoxy
bis(acetylacetonato)titanium, di-t-butoxy
bis(acetylacetonato)titanium, monoethoxy
tris(acetylacetonato)titanium, mono-n-propoxy
tris(acetylacetonato)titanium, mono-i-propoxy
tris(acetylacetonato)titanium, mono-n-butoxy
tris(acetylacetonato)titanium, mono-sec-butoxy
tris(acetylacetonato)titanium, mono-t-butoxy
tris(acetylacetonato)titanium, tetrakis(acetylacetonato)titanium,
triethoxy mono(ethylacetoacetate)titanium, tri-n-propoxy
mono(ethylacetoacetate)titanium, tri-i-propoxy
mono(ethylacetoacetate)titanium, tri-n-butoxy
mono(ethylacetoacetate)titanium, tri-sec-butoxy
mono(ethylacetoacetate)titanium, tri-t-butoxy
mono(ethylacetoacetate)titanium, diethoxy
bis(ethylacetoacetate)titanium, di-n-propoxy
bis(ethylacetoacetate)titanium, di-i-propoxy
bis(ethylacetoacetate)titanium, di-n-butoxy
bis(ethylacetoacetate)titanium, di-sec-butoxy
bis(ethylacetoacetate)titanium, di-t-butoxy
bis(ethylacetoacetate)titanium, monoethoxy
tris(ethylacetoacetate)titanium, mono-n-propoxy
tris(ethylacetoacetate)titanium, mono-i-propoxy
tris(ethylacetoacetate)titanium, mono-n-butoxy
tris(ethylacetoacetate)titanium, mono-sec-butoxy
tris(ethylacetoacetate)titanium, mono-t-butoxy
tris(ethylacetoacetate)titanium,
tetrakis(ethylacetoacetate)titanium,
mono(acetylacetonato)tris(ethylacetoacetate)titanium,
bis(acetylacetonato)bis(ethylacetoacetate)titanium, and
tris(acetylacetonato)mono(ethylacetoacetate)titanium; zirconium
chelate compounds, such as triethoxy
mono(acetylacetonato)zirconium, tri-n-propoxy
mono(acetylacetonato)zirconium, tri-i-propoxy
mono(acetylacetonato)zirconium, tri-n-butoxy
mono(acetylacetonato)zirconium, tri-sec-butoxy
mono(acetylacetonato)zirconium, tri-t-butoxy
mono(acetylacetonato)zirconium, diethoxy
bis(acetylacetonato)zirconium, di-n-propoxy
bis(acetylacetonato)zirconium, di-i-propoxy
bis(acetylacetonato)zirconium, di-n-butoxy
bis(acetylacetonato)zirconium, di-sec-butoxy
bis(acetylacetonato)zirconium, di-t-butoxy
bis(acetylacetonato)zirconium, monoethoxy
tris(acetylacetonato)zirconium, mono-n-propoxy
tris(acetylacetonato)zirconium, mono-i-propoxy
tris(acetylacetonato)zirconium, mono-n-butoxy
tris(acetylacetonato)zirconium, mono-sec-butoxy
tris(acetylacetonato)zirconium, mono-t-butoxy
tris(acetylacetonato)zirconium, tetrakis(acetylacetonato)zirconium,
triethoxy mono(ethylacetoacetate)zirconium, tri-n-propoxy
mono(ethylacetoacetate)zirconium, tri-i-propoxy
mono(ethylacetoacetate)zirconium, tri-n-butoxy
mono(ethylacetoacetate)zirconium, tri-sec-butoxy
mono(ethylacetoacetate)zirconium, tri-t-butoxy
mono(ethylacetoacetate)zirconium, diethoxy
bis(ethylacetoacetate)zirconium, di-n-propoxy
bis(ethylacetoacetate)zirconium, di-i-propoxy
bis(ethylacetoacetate)zirconium, di-n-butoxy
bis(ethylacetoacetate)zirconium, di-sec-butoxy
bis(ethylacetoacetate)zirconium, di-t-butoxy
bis(ethylacetoacetate)zirconium, monoethoxy
tris(ethylacetoacetate)zirconium, mono-n-propoxy
tris(ethylacetoacetate)zirconium, mono-i-propoxy
tris(ethylacetoacetate)zirconium, mono-n-butoxy
tris(ethylacetoacetate)zirconium, mono-sec-butoxy
tris(ethylacetoacetate)zirconium, mono-t-butoxy
tris(ethylacetoacetate)zirconium,
tetrakis(ethylacetoacetate)zirconium,
mono(acetylacetonato)tris(ethylacetoacetate)zirconium,
bis(acetylacetonato)bis(ethylacetoacetate)zirconium, and
tris(acetylacetonato)mono(ethylacetoacetate)zirconium; and aluminum
chelate compounds, such as tris(acetylacetonato)aluminum and
tris(ethylacetoacetate)aluminum.
Examples of the organic acid serving as the hydrolysis catalyst
include acetic acid, propionic acid, butanoic acid, pentanoic acid,
hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid,
decanoic acid, oxalic acid, maleic acid, methylmalonic acid, adipic
acid, sebacic acid, gallic acid, butyric acid, mellitic acid,
arachidonic acid, 2-ethylhexanoic acid, oleic acid, stearic acid,
linoleic acid, linolenic acid, salicylic acid, benzoic acid,
p-aminobenzoic acid, p-toluenesulfonic acid, benzenesulfonic acid,
monochloroacetic acid, dichloroacetic acid, trichloroacetic acid,
trifluoroacetic acid, formic acid, malonic acid, sulfonic acid,
phthalic acid, fumaric acid, citric acid, and tartaric acid.
Examples of the inorganic acid serving as the hydrolysis catalyst
include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric
acid, and phosphoric acid.
Examples of the organic base serving as the hydrolysis catalyst
include pyridine, pyrrole, piperazine, pyrrolidine, piperidine,
picoline, trimethylamine, triethylamine, monoethanolamine,
diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine,
triethanolamine, diazabicyclooctane, diazabicyclononane,
diazabicycloundecene, and tetramethylammonium hydroxide. Examples
of the inorganic base include ammonia, sodium hydroxide, potassium
hydroxide, barium hydroxide, and calcium hydroxide. Among these
catalysts, the metal chelate compounds, the organic acids, and the
inorganic acids are preferable, and these catalysts may be used
alone or in combination of two or more kinds thereof.
Examples of the organic solvent used for the hydrolysis include:
aliphatic hydrocarbon-based solvents, such as n-pentane, i-pentane,
n-hexane, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane,
n-octane, i-octane, cyclohexane, and methylcyclohexane; aromatic
hydrocarbon-based solvents, such as benzene, toluene, xylene,
ethylbenzene, trimethylbenzene, methylethylbenzene,
n-propylbenzene, i-propylbenzene, diethylbenzene, i-butylbenzene,
triethylbenzene, di-i-propylbenzene, n-amylnaphthalene, and
trimethylbenzene; monohydric alcohol-based solvents, such as
methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol,
sec-butanol, t-butanol, n-pentanol, i-pentanol, 2-methylbutanol,
sec-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol,
2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol,
heptanol-3, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl
alcohol, 2,6-dimethylheptanol-4, n-decanol, sec-undecyl alcohol,
trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl
alcohol, phenol, cyclohexanol, methylcyclohexanol,
3,3,5-trimethylcyclohexanol, benzyl alcohol, phenylmethylcarbinol,
diacetone alcohol, and cresol; polyhydric alcohol-based solvents,
such as ethylene glycol, propylene glycol, 1,3-butylene glycol,
pentanediol-2,4,2-methylpentanediol-2,4, hexanediol-2,5,
heptanediol-2,4,2-ethylhexanediol-1,3, diethylene glycol,
dipropylene glycol, triethylene glycol, tripropylene glycol, and
glycerol; ketone-based solvents, such as acetone, methyl ethyl
ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl
ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone,
ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-i-butyl ketone,
trimethylnonanone, cyclohexanone, methylcyclohexanone,
2,4-pentanedione, acetonylacetone, diacetone alcohol, acetophenone,
and fenchone; ether-based solvents, such as ethyl ether, i-propyl
ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene
oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane,
dimethyldioxane, ethylene glycol monomethyl ether, ethylene glycol
monoethyl ether, ethylene glycol diethyl ether, ethylene glycol
mono-n-butyl ether, ethylene glycol mono-n-hexyl ether, ethylene
glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether,
ethylene glycol dibutyl ether, diethylene glycol monomethyl ether,
diethylene glycol monoethyl ether, diethylene glycol diethyl ether,
diethylene glycol mono-n-butyl ether, diethylene glycol di-n-butyl
ether, diethylene glycol mono-n-hexyl ether, ethoxytriglycol,
tetraethylene glycol di-n-butyl ether, propylene glycol monomethyl
ether, propylene glycol monoethyl ether, propylene glycol
monopropyl ether, propylene glycol monobutyl ether, propylene
glycol monomethyl ether acetate, dipropylene glycol monomethyl
ether, dipropylene glycol monoethyl ether, dipropylene glycol
monopropyl ether, dipropylene glycol monobutyl ether, tripropylene
glycol monomethyl ether, tetrahydrofuran, and
2-methyltetrahydrofuran; ester-based solvents, such as diethyl
carbonate, methyl acetate, ethyl acetate, .gamma.-butyrolactone,
.gamma.-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl
acetate, i-butyl acetate, sec-butyl acetate, n-pentyl acetate,
sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate,
2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate,
cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate,
methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl
ether acetate, ethylene glycol monoethyl ether acetate, diethylene
glycol monomethyl ether acetate, diethylene glycol monoethyl ether
acetate, diethylene glycol mono-n-butyl ether acetate, propylene
glycol monomethyl ether acetate, propylene glycol monoethyl ether
acetate, propylene glycol monopropyl ether acetate, propylene
glycol monobutyl ether acetate, dipropylene glycol monomethyl ether
acetate, dipropylene glycol monoethyl ether acetate, glycol
diacetate, methoxytriglycol acetate, ethyl propionate, n-butyl
propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate,
methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate,
diethyl malonate, dimethyl phthalate, and diethyl phthalate;
nitrogen-containing solvents, such as N-methylformamide,
N,N-dimethylformamide, N,N-diethylformamide, acetamide,
N-methylacetamide, N,N-dimethylacetamide, N-methylpropionamide, and
N-methylpyrrolidone; and sulfur-containing solvents, such as
dimethyl sulfide, diethyl sulfide, thiophene, tetrahydrothiophene,
dimethyl sulfoxide, sulfolane, and 1,3-propanesultone. These
solvents may be used alone or in combination of two or more kinds
thereof.
In particular, ketone-based solvents, such as acetone, methyl ethyl
ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl
ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone,
ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-i-butyl ketone,
trimethylnonanone, cyclohexanone, methylcyclohexanone,
2,4-pentanedione, acetonylacetone, diacetone alcohol, acetophenone,
and fenchone, are preferable in terms of the preservation stability
of the solution.
Furthermore, bisphenol S or a bisphenol S derivative may be added
as an additive. The amount of bisphenol S or a bisphenol S
derivative added is 0.01 part by mass to 20 parts by mass, 0.01
part by mass to 10 parts by mass, or 0.01 part by mass to 5 parts
by mass with respect to 100 parts by mass of
polyorganosiloxane.
Preferable examples of the bisphenol S and the bisphenol S
derivative are as follows.
##STR00016## ##STR00017## ##STR00018##
The resist underlayer film-forming composition of the present
invention may include a curing catalyst. The curing catalyst acts
as a curing catalyst when a coating film including a
polyorganosiloxane formed of a hydrolysis-condensation product is
heated and cured.
As the curing catalyst, ammonium salts, phosphines, phosphonium
salts, and sulfonium salts may be used.
Examples of the ammonium salts include: a quaternary ammonium salt
having a structure of Formula (D-1):
##STR00019## (where m is an integer of 2 to 11; n is an integer of
2 or 3; R.sup.21 is an alkyl group or an aryl group; and
Y.sub.A.sup.- is an anion);
a quaternary ammonium salt having a structure of Formula (D-2):
R.sup.22R.sup.23R.sup.24R.sup.25N.sup.+ Y.sub.A.sup.- Formula (D-2)
(where R.sup.22, R.sup.23, R.sup.24, and R.sup.25 are each an alkyl
group or an aryl group; N is a nitrogen atom; Y.sub.A.sup.- is an
anion; and each of R.sup.22, R.sup.23, R.sup.24, and R.sup.25 is
bonded to the nitrogen atom through a C--N bond);
a quaternary ammonium salt having a structure of Formula (D-3):
##STR00020## (where R.sup.26 and R.sup.27 are each an alkyl group
or an aryl group; and Y.sub.A.sup.- is an anion);
a quaternary ammonium salt having a structure of Formula (D-4):
##STR00021## (where R.sup.28 is an alkyl group or an aryl group;
and Y.sub.A.sup.- is an anion);
a quaternary ammonium salt having a structure of Formula (D-5):
##STR00022## (where R.sup.29 and R.sup.30 are each an alkyl group
or an aryl group; and Y.sub.A.sup.- is an anion); and a tertiary
ammonium salt having a structure of Formula (D-6):
##STR00023## (where m is an integer of 2 to 11; n is an integer of
2 or 3; H is a hydrogen atom; and Y.sub.A.sup.- is an anion).
Examples of the phosphonium salts include a quaternary phosphonium
salt of Formula (D-7):
R.sup.31R.sup.32R.sup.33R.sup.34P.sup.+Y.sub.A.sup.- Formula (D-7)
(where R.sup.31, R.sup.32, R.sup.33, and R.sup.34 are each an alkyl
group or an aryl group; P is a phosphorus atom; Y.sub.A.sup.- is an
anion; and each of R.sup.31, R.sup.32, R.sup.33, and R.sup.34 is
bonded to the phosphorus atom through a C--P bond).
Examples of the sulfonium salts include a tertiary sulfonium salt
of Formula (D-8): R.sup.35R.sup.36R.sup.37S.sup.+Y.sub.A.sup.-
Formula (D-8) (where R.sup.35, R.sup.36, and R.sup.37 are each an
alkyl group or an aryl group; S is a sulfur atom; Y.sub.A.sup.- is
an anion; and each of R.sup.35, R.sup.36, and R.sup.37 is bonded to
the sulfur atom through a C--S bond).
The compound of Formula (D-1) above is a quaternary ammonium salt
derived from an amine, and, in Formula (D-1), m is an integer of 2
to 11 and n is an integer of 2 or 3. R.sup.21 of this quaternary
ammonium salt is a C.sub.1-18, preferably C.sub.2-10 alkyl or aryl
group. Examples of R.sup.21 include linear alkyl groups, such as
ethyl group, propyl group, and butyl group, benzyl group,
cyclohexyl group, cyclohexylmethyl group, and dicyclopentadienyl
group. Examples of the anion (Y.sub.A.sup.-) include: halide ions,
such as chloride ion (Cl.sup.-), bromide ion (Br.sup.-), and iodide
ion (I.sup.-); and acid groups, such as carboxylate (--COO.sup.-),
sulfonate (--SO.sub.3), and alcoholate (--O.sup.-).
The compound of Formula (D-2) above is a quaternary ammonium salt
having a structure of
R.sup.22R.sup.23R.sup.24R.sup.25N.sup.+Y.sub.A.sup.-. R.sup.22,
R.sup.23, R.sup.24, and R.sup.25 of this quaternary ammonium salt
are each a C.sub.1-18 alkyl or aryl group, or a silane compound
bonded to a silicon atom through a Si--C bond. Examples of the
anion (Y.sub.A) include: halide ions, such as chloride ion
(Cl.sup.-), bromide ion (Br.sup.-), and iodide ion (I.sup.-); and
acid groups, such as carboxylate (--COO.sup.-), sulfonate
(--SO.sub.3.sup.-), and alcoholate (--O.sup.-). This quaternary
ammonium salt is commercially available, and examples of this
quaternary ammonium salt include tetramethylammonium acetate,
tetrabutylammonium acetate, benzyltriethylammonium chloride,
benzyltriethylammonium bromide, methyltrioctylammonium chloride,
benzyltributylammonium chloride, and benzyltrimethylammonium
chloride.
The compound of Formula (D-3) is a quaternary ammonium salt derived
from 1-substituted imidazole, and, in Formula (D-3), R.sup.26 and
R.sup.27 are each a C.sub.1-18 alkyl or aryl group, and the sum
total of the number of carbon atoms of R.sup.26 and R.sup.27 is
preferably 7 or more. Examples of R.sup.26 include methyl group,
ethyl group, propyl group, phenyl group, and benzyl group. Examples
of R.sup.27 include benzyl group, octyl group, and octadecyl group.
Examples of the anion (Y.sub.A.sup.-) include: halide ions, such as
chloride ion (Cl.sup.-), bromide ion (Br.sup.-), and iodide ion
(I.sup.-); and acid groups, such as carboxylate (--COO.sup.-),
sulfonate (--SO.sub.3.sup.-), and alcoholate (--O.sup.-). Although
this compound is commercially available, the compound can be
produced by, for example, a reaction between an imidazole-based
compound, such as 1-methylimidazole or 1-benzylimidazole, and an
alkyl or aryl halide, such as benzyl bromide or methyl bromide.
The compound of Formula (D-4) above is a quaternary ammonium salt
derived from pyridine, and in Formula (D-4), R.sup.28 is a
C.sub.1-18, preferably C.sub.4-18 alkyl or aryl group, and examples
of R.sup.28 include butyl group, octyl group, benzyl group, and
lauryl group. Examples of the anion (Y.sub.A.sup.-) include: halide
ions, such as chloride ion (Cl.sup.-), bromide ion (Br.sup.-), and
iodide ion (I.sup.-); and acid groups, such as carboxylate
(--COO.sup.-), sulfonate (--SO.sub.3.sup.-), and alcoholate
(--O.sup.-). Although this compound is commercially available, the
compound can be produced by, for example, a reaction between
pyridine and an alkyl or aryl halide, such as lauryl chloride,
benzyl chloride, benzyl bromide, methyl bromide, or octyl bromide.
Examples of this compound include N-laurylpyridinium chloride and
N-benzylpyridinium bromide.
The compound of Formula (D-5) above is a quaternary ammonium salt
derived from a substituted pyridine, typified by picoline. In
Formula (D-5), R.sup.29 is a C.sub.1-18, preferably C.sub.4-18
alkyl or aryl group, and examples of R.sup.29 include methyl group,
octyl group, lauryl group, and benzyl group. R.sup.30 is a
C.sub.1-18 alkyl or aryl group, and, for example, in the case where
the compound is a quaternary ammonium salt derived from picoline,
R.sup.30 is a methyl group. Examples of the anion (Y.sub.A.sup.-)
include: halide ions, such as chloride ion (Cl.sup.-), bromide ion
(Br.sup.-), and iodide ion (I.sup.-); and acid groups, such as
carboxylate (--COO.sup.-), sulfonate (--SO.sub.3.sup.-), and
alcoholate (--O.sup.-). Although this compound is commercially
available, the compound can be produced by, for example, a reaction
between a substituted pyridine, such as picoline, and an alkyl or
aryl halide, such as methyl bromide, octyl bromide, lauryl
chloride, benzyl chloride, or benzyl bromide. Examples of this
compound include N-benzylpicolinium chloride, N-benzylpicolinium
bromide, and N-laurylpicolinium chloride.
The compound of Formula (D-6) is a tertiary ammonium salt derived
from an amine, and, in Formula (D-6), m is an integer of 2 to 11
and n is an integer of 2 or 3. Examples of the anion (Y.sub.A)
include: halide ions, such as chloride ion (Cl.sup.-), bromide ion
(Br.sup.-), and iodide ion (I.sup.-); and acid groups, such as
carboxylate (--COO.sup.-), sulfonate (--SO.sub.3.sup.-), and
alcoholate (--O.sup.-). The compound can be produced by, for
example, a reaction between an amine and a weak acid, such as a
carboxylic acid or phenol. Examples of the carboxylic acid include
formic acid and acetic acid. In the case of using formic acid, the
anion (Y.sub.A.sup.-) is (HCOO.sup.-). In the case of using acetic
acid, the anion (Y.sub.A.sup.-) is (CH.sub.3COO.sup.-).
Alternatively, in the case of phenol, the anion (Y.sub.A.sup.-) is
(C.sub.6H.sub.5O).
The compound of Formula (D-7) above is a quaternary phosphonium
salt having a structure of
R.sup.31R.sup.32R.sup.33.sub.R.sup.34P.sup.+Y.sub.A.sup.-.
R.sup.31, R.sup.32, R.sup.33, and R.sup.34 are each a C.sub.1-18
alkyl or aryl group, or a silane compound bonded to a silicon atom
through a Si--C bond. Three of the four substituents, R.sup.31 to
R.sup.34, are preferably a phenyl group or a substituted phenyl
group, and examples of the substituents include phenyl group and
tolyl group. The remaining one substituent is a C.sub.1-18 alkyl or
aryl group, or a silane compound bonded to a silicon atom through a
Si--C bond. Examples of the anion (Y.sub.A.sup.-) include: halide
ions, such as chloride ion (Cl.sup.-), bromide ion (Br.sup.-), and
iodide ion (I.sup.-); and acid groups, such as carboxylate
(--COO.sup.-), sulfonate (--SO.sub.3.sup.-), and alcoholate
(--O.sup.-). This compound is commercially available, and examples
of the compound include: tetraalkylphosphonium halides, such as
tetra-n-butylphosphonium halides and tetra-n-propylphosphonium
halides; trialkylbenzylphosphonium halides, such as
triethylbenzylphosphonium halides; triphenylmonoalkylphosphonium
halides, such as triphenylmethylphosphonium halides and
triphenylethylphosphonium halides; triphenylbenzylphosphonium
halides; tetraphenylphosphonium halides;
tritolylmonoarylphosphonium halides; and
tritolylmonoalkylphosphonium halides, (in which a halogen atom is a
chlorine atom or a bromine atom). In particular,
triphenylmonoalkylphosphonium halides, such as
triphenylmethylphosphonium halides and triphenylethylphosphonium
halides; triphenylmonoarylphosphonium halides, such as
triphenylbenzylphosphonium halides; tritolylmonoarylphosphonium
halides, such as tritolylmonophenylphosphonium halides; and
tritolylmonoalkylphosphonium halides, such as
tritolylmonomethylphosphonium halides (in which a halogen atom is a
chlorine atom or a bromine atom), are preferable.
Examples of the phosphines include: primary phosphines, such as
methylphosphine, ethylphosphine, propylphosphine,
isopropylphosphine, isobutylphosphine, and phenylphosphine;
secondary phosphines, such as dimethylphosphine, diethylphosphine,
diisopropylphosphine, diisoamylphosphine, and diphenylphosphine;
and tertiary phosphines, such as trimethylphosphine,
triethylphosphine, triphenylphosphine, methyldiphenylphosphine, and
dimethylphenylphosphine.
The compound of Formula (D-8) above is a tertiary sulfonium salt
having a structure of R.sup.35R.sup.36R.sup.37S.sup.+Y.sub.A.sup.-.
R.sup.35, R.sup.36, and R.sup.37 are each a C.sub.1-18 alkyl or
aryl group, or a silane compound bonded to a silicon atom through a
Si--C bond. Three of the four substituents, R.sup.35 to R.sup.37,
are preferably a phenyl group or a substituted phenyl group, and
examples of the substituents include phenyl group and tolyl group.
The remaining one substituent is a C.sub.1-18 alkyl or aryl group.
Examples of the anion (Y.sub.A.sup.-) include: halide ions, such as
chloride ion (Cl.sup.-), bromide ion (Br.sup.-), and iodide ion
(I.sup.-); and acid groups, such as carboxylate (--COO), sulfonate
(--SO.sub.3.sup.-), alcoholate (-OD, maleic acid anion, and nitric
acid anion. This compound is commercially available, and examples
of the compound include: tetraalkylsulfonium halides, such as
tri-n-butylsulfonium halides and tri-n-propylsulfonium halides;
trialkylbenzylsulfonium halides, such as diethylbenzylsulfonium
halides; diphenylmonoalkylsulfonium halides, such as
diphenylmethylsulfonium halides and diphenylethylsulfonium halides;
and triphenylsulfonium halides (in which a halogen atom is a
chlorine atom or a bromine atom); tetraalkylphosphonium
carboxylates, such as tri-n-butylsulfonium carboxylate and
tri-n-propylsulfonium carboxylate; trialkylbenzylsulfonium
carboxylates, such as diethylbenzylsulfonium carboxylate;
diphenylmonoalkylsulfonium carboxylates, such as
diphenylmethylsulfonium carboxylate and diphenylethylsulfonium
carboxylate; and triphenylsulfonium carboxylate. Triphenylsulfonium
halides and triphenylsulfonium carboxylate are preferably used.
Furthermore, in the present invention, a nitrogen-containing silane
compound may be added as a curing catalyst. Examples of the
nitrogen-containing silane compound include an
imidazole-ring-containing silane compound, such as
N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole.
The amount of the curing catalyst added is 0.01 part by mass to 10
parts by mass, 0.01 part by mass to 5 parts by mass, or 0.01 part
by mass to 3 parts by mass with respect to 100 parts by mass of
polyorganosiloxane.
From a hydrolysis-condensation product (a polymer) obtained by
hydrolyzing and condensing a hydrolyzable silane using a catalyst
in a solvent, alcohols as by-products, the used hydrolysis
catalyst, and water can be removed at the same time by, for
example, distillation under reduced pressure. Furthermore, an acid
and base catalyst each used in the hydrolysis can be removed by
neutralization or ion exchange. In the resist underlayer
film-forming composition for lithography of the present invention,
an organic acid, water, and alcohols, or a combination thereof may
be added to the resist underlayer film-forming composition
including the hydrolysis-condensation product for the purpose of
stabilization.
Examples of the organic acid include oxalic acid, malonic acid,
methylmalonic acid, succinic acid, maleic acid, malic acid,
tartaric acid, phthalic acid, citric acid, glutaric acid, citric
acid, lactic acid, and salicylic acid. Among these, oxalic acid and
maleic acid are preferable. The amount of the organic acid added is
0.1 part by mass to 5.0 parts by mass with respect to 100 parts by
mass of the condensation product (polyorganosiloxane). Furthermore,
pure water, ultrapure water, and ion exchange water may be used as
the water to be added, and the amount of the water added may be 1
part by mass to 20 parts by mass with respect to 100 parts by mass
of the resist underlayer film-forming composition.
As the alcohol to be added, alcohol that easily disperses by
heating after the application is preferable, and examples of the
alcohol include methanol, ethanol, propanol, isopropanol
(2-propanol), and butanol. The amount of the alcohol added may be 1
part by mass to 20 parts by mass with respect to 100 parts by mass
of the resist underlayer film-forming composition.
Besides the above-mentioned components, the underlayer film-forming
composition for lithography of the present invention may contain an
organic polymer compound, a photoacid generator, and a surfactant,
as necessary.
The use of an organic polymer compound allows the adjustment of the
dry etching rate (the amount of reduction in film thickness per
unit time), the attenuation coefficient, and the refractive index
of a resist underlayer film formed from the underlayer film-forming
composition for lithography of the present invention.
The organic polymer compound is not limited to a particular
compound, and various kinds of organic polymers may be used. For
example, polycondensation polymers and addition polymerization
polymers may be used. The addition polymerization polymers and the
polycondensation polymers to be used include polyesters,
polystyrenes, polyimides, acrylic polymers, methacrylic polymers,
polyvinyl ethers, phenol novolacs, naphthol novolacs, polyethers,
polyamides, and polycarbonates may be used. Organic polymers having
aromatic ring structures that function as a light absorbing
portion, such as a benzene ring, a naphthalene ring, an anthracene
ring, a triazine ring, a quinoline ring, and a quinoxaline ring,
are preferably used.
Examples of such organic polymer compound include: addition
polymerization polymers including, as a structural unit thereof,
addition polymerizable monomers, such as benzyl acrylate, benzyl
methacrylate, phenyl acrylate, naphthyl acrylate, anthryl
methacrylate, anthrylmethyl methacrylate, styrene, hydroxystyrene,
benzyl vinyl ether, and N-phenylmaleimide; and polycondensation
polymers, such as phenol novolacs and naphthol novolacs.
In the case where an addition polymerization polymer is used as the
organic polymer compound, the polymer compound may be a homopolymer
or a copolymer. For the manufacture of the addition polymerization
polymer, an addition polymerizable monomer is used. Examples of
such addition polymerizable monomer include acrylic acid,
methacrylic acid, an acrylic ester compound, a methacrylic ester
compound, an acrylamide compound, a methacrylamide compound, a
vinyl compound, a styrene compound, a maleimide compound, a maleic
anhydride, and acrylonitrile.
Examples of the acrylic ester compound include methyl acrylate,
ethyl acrylate, normal hexyl acrylate, isopropyl acrylate,
cyclohexyl acrylate, benzyl acrylate, phenyl acrylate,
anthrylmethyl acrylate, 2-hydroxyethyl acrylate,
3-chloro-2-hydroxypropyl acrylate, 2-hydroxypropyl acrylate,
2,2,2-trifluoroethyl acrylate, 2,2,2-trichloroethyl acrylate,
2-bromoethyl acrylate, 4-hydroxybutyl acrylate, 2-methoxyethyl
acrylate, tetrahydrofurfuryl acrylate, 2-methyl-2-adamantyl
acrylate, 5-acryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone,
3-acryloxypropyltriethoxysilane, and glycidyl acrylate.
Examples of the methacrylic ester compound include methyl
methacrylate, ethyl methacrylate, normal hexyl methacrylate,
isopropyl methacrylate, cyclohexyl methacrylate, benzyl
methacrylate, phenyl methacrylate, anthrylmethyl methacrylate,
2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate,
2,2,2-trifluoroethyl methacrylate, 2,2,2-trichloroethyl
methacrylate, 2-bromoethyl methacrylate, 4-hydroxybutyl
methacrylate, 2-methoxyethyl methacrylate, tetrahydrofurfuryl
methacrylate, 2-methyl-2-adamantyl methacrylate,
5-methacryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone,
3-methacryloxypropyltriethoxysilane, glycidyl methacrylate,
2-phenylethyl methacrylate, hydroxyphenyl methacrylate, and
bromophenyl methacrylate.
Examples of the acrylamide compound include acrylamide,
N-methylacrylamide, N-ethylacrylamide, N-benzylacrylamide,
N-phenylacrylamide, N,N-dimethylacrylamide, and
N-anthrylacrylamide.
Examples of the methacrylamide compound include methacrylamide,
N-methylmethacrylamide, N-ethylmethacrylamide,
N-benzylmethacrylamide, N-phenylmethacrylamide,
N,N-dimethylmethacrylamide, and N-anthrylacrylamide.
Examples of the vinyl compound include vinyl alcohol,
2-hydroxyethyl vinyl ether, methyl vinyl ether, ethyl vinyl ether,
benzyl vinyl ether, vinylacetic acid, vinyl trimethoxy silane,
2-chloroethyl vinyl ether, 2-methoxyethyl vinyl ether, vinyl
naphthalene, and vinyl anthracene.
Examples of the styrene compound include styrene, hydroxystyrene,
chlorostyrene, bromostyrene, methoxystyrene, cyanostyrene, and
acetylstyrene.
Examples of the maleimide compound include maleimide,
N-methylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide,
N-benzylmaleimide, and N-hydroxyethylmaleimide.
In the case of using a polycondensation polymer as the polymer,
examples of such polymer include a polycondensation polymer of a
glycol compound and a dicarboxylic acid compound. Examples of the
glycol compound include diethylene glycol, hexamethylene glycol,
and butylene glycol. Examples of the dicarboxylic acid compound
include succinic acid, adipic acid, terephthalic acid, and maleic
anhydride.
Examples of the polycondensation polymer include polyesters,
polyamides, and polyimides, such as polypyromellitic imides,
poly(p-phenyleneterephthalamide)s, polybutylene terephthalates, and
polyethylene terephthalates.
In the case where the organic polymer compound has a hydroxy group,
this hydroxy group can cause a crosslinking reaction with a
polyorganosiloxane.
As the organic polymer compound, a polymer compound having a weight
average molecular weight of, for example, 1,000 to 1,000,000, 3,000
to 300,000, 5,000 to 200,000, or 10,000 to 100,000 may be used.
The organic polymer compound may be used alone or in combination of
two or more kinds thereof.
In the case of using the organic polymer compound, the amount of
the organic polymer compound used is 1 part by mass to 200 parts by
mass, 5 parts by mass to 100 parts by mass, 10 parts by mass to 50
parts by mass, or 20 parts by mass to 30 parts by mass with respect
to 100 parts by mass of the condensation product
(polyorganosiloxane).
The resist underlayer film-forming composition of the present
invention may include an acid generator.
Examples of the acid generator include thermal acid generators and
photoacid generators.
Photoacid generators generate an acid at the time of the
light-exposure of a resist. Thus, the acidity of an underlayer film
can be adjusted. This is one method for adjusting the acidity of an
underlayer film to the acidity of a resist serving as an upper
layer of the underlayer film. Furthermore, the adjustment of
acidity of an underlayer film allows the pattern shape of a resist
formed as an upper layer of the underlayer film to be adjusted.
Examples of the photoacid generator included in the resist
underlayer film-forming composition of the present invention
include an onium salt compound, a sulfonimide compound, and a
disulfonyldiazomethane compound.
Examples of the onium salt compound include: iodonium salt
compounds, such as diphenyliodonium hexafluorophosphate,
diphenyliodonium trifluoromethanesulfonate, diphenyliodonium
nonafluoro normal butanesulfonate, diphenyliodonium perfluoro
normal octanesulfonate, diphenyliodonium camphorsulfonate,
bis(4-tert-butylphenyl)iodonium camphorsulfonate, and
bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate; and
sulfonium salt compounds, such as triphenylsulfonium
hexafluoroantimonate, triphenylsulfonium nonafluoro normal
butanesulfonate, triphenylsulfonium camphorsulfonate, and
triphenylsulfonium trifluoromethanesulfonate.
Examples of the sulfonimide compound include
N-(trifluoromethanesulfonyloxy)succinimide, N-(nonafluoro normal
butane sulfonyloxy)succinimide, N-(camphorsulfonyloxy)succinimide,
and N-(trifluoromethanesulfonyloxy)naphthalimide.
Examples of the disulfonyldiazomethane compound include
bis(trifluoromethylsulfonyl)diazomethane,
bis(cyclohexylsulfonyl)diazomethane,
bis(phenylsulfonyl)diazomethane,
bis(p-toluenesulfonyl)diazomethane,
bis(2,4-dimethylbenzenesulfonyl)diazomethane, and methyl
sulfonyl-p-toluenesulfonyldiazomethane.
The photoacid generator may be used alone or in combination of two
or more kinds thereof.
In the case of using the photoacid generator, the amount of the
photoacid generator used is 0.01 part by mass to 15 parts by mass,
0.1 part by mass to 10 parts by mass, or 0.5 part by mass to 1 part
by mass with respect to 100 parts by mass of the condensation
product (polyorganosiloxane).
Surfactants effectively suppress the formation of pinholes and
striations when the resist underlayer film-forming composition for
lithography of the present invention is applied to a substrate.
Examples of a surfactant included in the resist underlayer
film-forming composition of the present invention include: nonionic
surfactants, such as polyoxyethylene alkyl ethers including
polyoxyethylene lauryl ether, polyoxyethylene stearyl ether,
polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether,
polyoxyethylene alkylallyl ethers including polyoxyethylene
octylphenol ether and polyoxyethylene nonylphenol ether,
polyoxyethylene-polyoxypropylene block copolymers, sorbitan fatty
acid esters, including sorbitan monolaurate, sorbitan
monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan
trioleate, and sorbitan tristearate, polyoxyethylene sorbitan fatty
acid esters, including polyoxyethylene sorbitan monolaurates,
polyoxyethylene sorbitan monopalmitates, polyoxyethylene sorbitan
monostearates, polyoxyethylene sorbitan trioleates, and
polyoxyethylene sorbitan tristearates; fluorine-based surfactants,
such as the trade names EFTOP EF301, EF303, and EF352 (manufactured
by Tohkem Products Corporation), the trade names MEGAFAC F171,
F173, R-08, R-30, R-30N, and R-40LM (manufactured by DIC
Corporation), Fluorad FC430 and FC431 (manufactured by Sumitomo 3M
Limited), the trade name Asahi Guard AG710 and the trade names
SURFLON S-382, SC101, SC102, SC103, SC104, SC105, and SC106
(manufactured by Asahi Glass Co., Ltd.); and an organosiloxane
polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). These
surfactants may be used alone or in combination of two or more
kinds thereof. In the case of using the surfactant, the amount of
the surfactant used is 0.0001 part by mass to 5 parts by mass,
0.001 part by mass to 1 part by mass, or 0.01 part by mass to 1
part by mass with respect to 100 parts by mass of the condensation
product (polyorganosiloxane).
Furthermore, to the resist underlayer film-forming composition of
the present invention, for example, a rheology controlling agent
and an adhesion assistant may be added. A rheology controlling
agent effectively improves the fluidity of the underlayer
film-forming composition. An adhesion assistant effectively
improves the adhesion between a semiconductor substrate or a resist
and an underlayer film.
As the solvent used for the resist underlayer film-forming
composition of the present invention, a solvent capable of
dissolving the above-mentioned solid contents may be used without
particular limitations. Examples of such solvent include
methylcellosolve acetate, ethylcellosolve acetate, propylene
glycol, propylene glycol monomethyl ether, propylene glycol
monoethyl ether, methyl isobutyl carbinol, propylene glycol
monobutyl ether, propylene glycol monomethyl ether acetate,
propylene glycol monoethyl ether acetate, propylene glycol
monopropyl ether acetate, propylene glycol monobutyl ether acetate,
toluene, xylene, methyl ethyl ketone, cyclopentanone,
cyclohexanone, ethyl 2-hydroxypropionate, ethyl
2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl
hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl
3-methoxypropinoate, ethyl 3-methoxypropionate, ethyl
3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate,
ethyl pyruvate, ethylene glycol monomethyl ether, ethylene glycol
monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol
monobutyl ether, ethylene glycol monomethyl ether acetate, ethylene
glycol mooethyl ether acetate, ethylene glycol monopropyl ether
acetate, ethylene glycol monobutyl ether acetate, diethylene glycol
dimethyl ether, diethylene glycol diethyl ether, diethylene glycol
dipropyl ether, diethylene glycol dibutyl ether, propylene glycol
monomethyl ether, propylene glycol dimethyl ether, propylene glycol
diethyl ether, propylene glycol dipropyl ether, propylene glycol
dibutyl ether, ethyl lactate, propyl lactate, isopropyl lactate,
butyl lactate, isobutyl lactate, methyl formate, ethyl formate,
propyl formate, isopropyl formate, butyl formate, isobutyl formate,
amyl formate, isoamyl formate, methyl acetate, ethyl acetate, amyl
acetate, isoamyl acetate, hexyl acetate, methyl propionate, ethyl
propionate, propyl propionate, isopropyl propionate, butyl
propionate, isobutyl propionate, methyl butyrate, ethyl butyrate,
propyl butyrate, isopropyl butyrate, butyl butyrate, isobutyl
butyrate, ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate,
methyl 3-methoxy-2-methylpropionate, methyl
2-hydroxy-3-methybutyrate, ethyl methoxyacetate, ethyl
ethoxyacetate, methyl 3-methoxypropionate, ethyl
3-ethoxypropionate, ethyl 3-methoxy propionate, 3-methoxybutyl
acetate, 3-methoxypropyl acetate, 3-methyl-3-methoxybutyl acetate,
3-methyl-3-methoxybutyl propionate, 3-methyl-3-methoxybutyl
butyrate, methyl acetoacetate, toluene, xylene, methyl ethyl
ketone, methyl propyl ketone, methyl butyl ketone, 2-heptanone,
3-heptanone, 4-heptanone, cyclohexanone, N,N-dimethylformamide,
N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone,
4-methyl-2-pentanol, and .gamma.-butyrolactone. These solvents may
be used alone or in combination of two or more kinds thereof.
Hereinafter, the use of the resist underlayer film-forming
composition of the present invention is described.
Using the resist underlayer film-forming composition of the present
invention, a resist underlayer film is formed on a substrate by
application, or is formed via an organic underlayer film on a
substrate by application onto the organic underlayer film, and
then, a resist film (for example, photoresist or electron beam
resist) is formed on the resist underlayer film. Then, a resist
pattern is formed by exposure and development. Using the resist
pattern, the resist underlayer film is dry-etched to perform the
transfer of the pattern, and the substrate is processed using the
pattern, or the organic underlayer film is etched to perform the
transfer of the pattern, and the substrate is processed using the
organic underlayer film.
In the formation of a fine pattern, the film thickness of a resist
tends to be made thinner for the purpose of preventing pattern
collapse. Due to such a thinner resist film, the etching rate of
dry etching for transferring a pattern to a film presents under the
resist film needs to be higher than the etching rate of the upper
layer film in order to perform the transfer of the pattern. In the
present invention, a resist underlayer film (containing an
inorganic silicon-based compound) of the present invention is
coated on a substrate via an organic underlayer film or not via an
organic underlayer film, and a resist film (an organic resist film)
is coated thereon in this order. Depending on a selected etching
gas, a film of an organic component and a film of an inorganic
component considerably differ in dry etching rate. With the use of
an oxygen-based gas, a film of an organic component is dry-etched
at a higher rate. In contrast, with the use of a halogen-containing
gas, a film of an inorganic component is dry-etched at a higher
rate.
For example, a resist pattern is formed, and a resist underlayer
film of the present invention under the resist pattern is
dry-etched using a halogen-containing gas to transfer the resist
pattern to the resist underlayer film. Using the resist pattern
transferred to the resist underlayer film, a substrate is processed
using a halogen-containing gas. Alternatively, using the resist
underlayer film to which the resist pattern is transferred, an
organic underlayer film present under the resist underlayer film is
dry-etched using an oxygen-based gas to transfer the resist pattern
to the organic underlayer film. Using the organic underlayer film
to which the resist pattern is transferred, a substrate is
processed using a halogen-containing gas.
Here, onto a substrate used for the manufacture of a semiconductor
device (for example, a silicon wafer substrate, a
silicon/silicon-dioxide coated substrate, a silicon nitride
substrate, a glass substrate, an ITO substrate, a polyimide
substrate, or a low dielectric constant material (low-k material)
coated substrate), the resist underlayer film-forming composition
of the present invention is applied by appropriate application
means, such as a spinner and a coater, followed by baking to form a
resist underlayer film. The baking is performed under the
conditions appropriately selected from heating temperatures of
80.degree. C. to 250.degree. C. and heating duration of 0.3 minute
to 60 minutes. The baking temperature is preferably 150.degree. C.
to 250.degree. C., and the heating duration is preferably 0.5
minute to 2 minutes. Here, the thickness of the underlayer film
formed is, for example, 10 nm to 1,000 nm, 20 nm to 500 nm, 50 nm
to 300 nm, or 100 nm to 200 nm.
Next, a photoresist layer, for example, is formed on the resist
underlayer film. The photoresist layer can be formed by a
well-known process, that is, the application of a solution of a
photoresist composition onto the underlayer film, followed by
baking. The film thickness of the photoresist layer is, for
example, 50 nm to 10,000 nm, 100 nm to 2,000 nm, or 200 nm to 1,000
nm.
In the present invention, an organic underlayer film can be formed
on a substrate, the resist underlayer film of the present invention
can then be formed on the organic underlayer film, and furthermore,
a photoresist can be coated on the resist underlayer film. This
allows the pattern width of the photoresist to be narrower, and
accordingly, even when the photoresist is applied thinly for the
purpose of preventing pattern collapse, selecting an appropriate
etching gas allows the substrate to be processed. For example, the
use of a fluorine-based gas as an etching gas, which results in a
significantly high etching rate for a photoresist, allows the
resist underlayer film of the present invention to be processed. In
contrast, the use of an oxygen-based gas as an etching gas, which
results in a significantly high etching rate for the resist
underlayer film of the present invention, allows an organic
underlayer film to be processed. Furthermore, the use of a
fluorine-based gas as an etching gas, which results in a
significantly high rate for the organic underlayer film, allows a
substrate to be processed.
The photoresist formed on the resist underlayer film of the present
invention is not limited to a particular one as long as the
photoresist is sensitive to light used for exposure. Both negative
and positive photoresists may be used. Examples of the photoresist
include a positive photoresist formed of a novolac resin and a
1,2-naphthoquinone diazide sulfonic acid ester; a chemically
amplified photoresist formed of a binder having a group that is
decomposed by acid to increase an alkali dissolution rate and a
photoacid generator; a chemically amplified photoresist formed of a
low molecular weight compound that is decomposed by acid to
increase an alkali dissolution rate of the photoresist, an
alkali-soluble binder, and a photoacid generator; and a chemically
amplified photoresist formed of a binder having a group that is
decomposed by acid to increase an alkali dissolution rate, a low
molecular weight compound that is decomposed by acid to increase an
alkali dissolution rate of the photoresist, and a photoacid
generator. Examples of the photoresists include the trade name
APEX-E, manufactured by Shipley, the trade name PAR710,
manufactured by Sumitomo Chemical Company, Limited, and the trade
name SEPR430, manufactured by Shin-Etsu Chemical Co., Ltd.
Furthermore, examples of the photoresists include
fluorine-atom-containing polymer-based photoresists described in
Proc. SPIE, Vol. 3999, 330-334 (2000), Proc. SPIE, Vol. 3999,
357-364 (2000), and Proc. SPIE, Vol. 3999, 365-374 (2000).
Next, light exposure is performed through a predetermined mask. For
the light exposure, for example, a KrF excimer laser (with a
wavelength of 248 nm), an ArF excimer laser (with a wavelength of
193 nm), or an F2 excimer laser (with a wavelength of 157 nm) may
be used. After the light exposure, post exposure bake may be
performed, if necessary. The post exposure bake is performed under
the conditions appropriately selected from heating temperatures of
70.degree. C. to 150.degree. C. and heating duration of 0.3 minute
to 10 minutes.
In the present invention, a resist for electron beam lithography or
a resist for EUV lithography may be used as a resist in place of a
photoresist. Both positive and negative electron beam resists may
be used. Examples of the electron beam resists include a chemically
amplified resist formed of an acid generator and a binder having a
group that is decomposed by acid to change an alkali dissolution
rate; a chemically amplified resist formed of an alkali-soluble
binder, an acid generator, and a low molecular weight compound that
is decomposed by acid to change an alkali dissolution rate of the
resist; a chemically amplified resist formed of an acid generator,
a binder having a group that is decomposed by acid to change an
alkali dissolution rate, and a low molecular weight compound that
is decomposed by acid to change an alkali dissolution rate of the
resist; a non-chemically amplified resist formed of a binder having
a group that is decomposed by an electron beam to change an alkali
dissolution rate; and a non-chemically amplified resist formed of a
binder having a portion that is cut by an electron beam to change
an alkali dissolution rate. Also, in the cases of using these
electron beam resists, a resist pattern can be formed using an
electron beam as an irradiation source in the same manner as in the
case of using a photoresist.
As the EUV resist, methacrylate resin-based resists,
methacrylate-polyhydroxystyrene hybrid resin-based resists, and
polyhydroxystyrene resin-based resists may be used. Both negative
and positive resists may be used as the EUV resist. Examples of the
resist include a chemically amplified resist including an acid
generator and a binder having a group decomposed by acid to change
an alkali dissolution rate; a chemically amplified resist including
an alkali-soluble binder, an acid generator, and a low molecular
weight compound decomposed by acid to change the alkali dissolution
rate of the resist; a chemically amplified resist including an acid
generator, a binder having a group decomposed by acid to change an
alkali dissolution rate, and a low molecular weight compound
decomposed by acid to change the alkali dissolution rate of the
resist; a non-chemically amplified resist including a binder having
a group decomposed by EUV light to change an alkali dissolution
rate; and a non-chemically amplified resist including a binder
having a portion cut by EUV light to change an alkali dissolution
rate.
Next, development is performed using a developing solution (for
example, an alkaline developing solution). Thus, for example, in
the case of using a positive photoresist, an exposed portion of the
photoresist is removed to form a pattern of the photoresist.
Examples of the developing solution include alkaline solutions,
such as: aqueous solutions of an alkali metal hydroxide, such as
potassium hydroxide and sodium hydroxide; aqueous solutions of a
quaternary ammonium hydroxide, such as tetramethyl ammonium
hydroxide, tetraethyl ammonium hydroxide, and choline; and aqueous
solutions of an amine, such as ethanolamine, propylamine, and
ethylenediamine. Furthermore, a surfactant or other substances may
be added to these developing solutions. The development conditions
are appropriately selected from temperatures of 5.degree. C. to
50.degree. C. and duration of 10 seconds to 600 seconds.
Furthermore, in the present invention, an organic solvent may be
used as a developing solution. After the light exposure,
development is performed using a developing solution (a solvent).
Thus, for example, in the case of using a positive photoresist, an
unexposed portion of the photoresist is removed to form a pattern
of the photoresist.
Examples of the developing solution include methyl acetate, butyl
acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl
acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene
glycol monomethyl ether acetate, ethylene glycol monoethyl ether
acetate, ethylene glycol monopropyl ether acetate, ethylene glycol
monobutyl ether acetate, ethylene glycol monophenyl ether acetate,
diethylene glycol monomethyl ether acetate, diethylene glycol
monopropyl ether acetate, diethylene glycol monoethyl ether
acetate, diethylene glycol monophenyl ether acetate, diethylene
glycol monobutyl ether acetate, 2-methoxy butyl acetate,
3-methoxybutyl acetate, 4-methoxybutyl acetate,
3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate,
propylene glycol monoethyl ether acetate, propylene glycol
monopropyl ether acetate, 2-ethoxy butyl acetate, 4-ethoxy butyl
acetate, 4-propoxy butyl acetate, 2-methoxy pentyl acetate,
3-methoxy pentyl acetate, 4-methoxy pentyl acetate,
2-methyl-3-methoxy pentyl acetate, 3-methyl-3-methoxy pentyl
acetate, 3-methyl-4-methoxy pentyl acetate, 4-methyl-4-methoxy
pentyl acetate, propylene glycol diacetate, methyl formate, ethyl
formate, butyl formate, propyl formate, ethyl lactate, butyl
lactate, propyl lactate, ethyl carbonate, propyl carbonate, butyl
carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl
pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl
propionate, ethyl propionate, propyl propionate, isopropyl
propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate,
methyl-3-methoxy propionate, ethyl-3-methoxy propionate,
ethyl-3-ethoxy propionate, and propyl-3-methoxy propionate.
Furthermore, a surfactant or other substances may be added to these
developing solutions. The development conditions are appropriately
selected from temperatures of 5.degree. C. to 50.degree. C. and
duration of 10 seconds to 600 seconds.
Then, using the thus-formed pattern of the photoresist (upper
layer) as a protective film, the photoresist underlayer film
(intermediate layer) of the present invention is removed.
Subsequently, using a film formed of the patterned photoresist and
the patterned resist underlayer film (intermediate layer) of the
present invention as protective films, an organic underlayer film
(lower layer) is removed. Finally, using the patterned resist
underlayer film (intermediate layer) of the present invention and
the patterned organic underlayer film (lower layer) as protective
films, a semiconductor substrate is processed.
First, a photoresist-removed portion of the resist underlayer film
(intermediate layer) of the present invention is removed by dry
etching to make a semiconductor substrate exposed. For the dry
etching of the resist underlayer film of the present invention,
gases, such as tetrafluoromethane (CF.sub.4), parfluorocyclobutane
(C.sub.4F.sub.8), parfluoropropane (C.sub.3F.sub.8),
trifluoromethane, carbon monoxide, argon, oxygen, nitrogen, sulfur
hexafluoride, difluoromethane, nitrogen trifluoride, chlorine
trifluoride, chlorine, trichloroborane, and dichloroborane may be
used. For the dry etching of the resist underlayer film, a
halogen-based gas is preferably used. With dry etching using a
halogen-based gas, a photoresist formed of an organic substance is
basically hard to remove. In contrast, the resist underlayer film
of the present invention that contains many silicon atoms is
promptly removed by a halogen-based gas. Thus, a reduction in the
film thickness of the photoresist that is associated with the dry
etching of the resist underlayer film can be suppressed. As a
result, a thinner photoresist film can be used. The dry etching of
the resist underlayer film is preferably performed using a
fluorine-based gas. Examples of the fluorine-based gas include
tetrafluoromethane (CF.sub.4), parfluorocyclobutane
(C.sub.4F.sub.8), parfluoropropane (C.sub.3F.sub.8),
trifluoromethane, and difluoromethane (CH.sub.2F.sub.2).
After that, using films formed of the patterned photoresist and the
patterned resist underlayer film of the present invention as
protective films, the organic underlayer film is removed. The dry
etching of the organic underlayer film (lower layer) is preferably
performed using an oxygen-based gas. This is because the resist
underlayer film of the present invention that contains many silicon
atoms is hard to remove by dry etching using an oxygen-based
gas.
Finally, a semiconductor substrate is processed. The processing of
the semiconductor substrate is preferably performed by dry etching
using a fluorine-based gas.
Examples of the fluorine-based gas include tetrafluoromethane
(CF.sub.4), parfluorocyclobutane (C.sub.4F.sub.8), parfluoropropane
(C.sub.3F.sub.8), trifluoromethane, and difluoromethane
(CH.sub.2F.sub.2).
Furthermore, on the resist underlayer film of the present
invention, an organic anti-reflective coating may be formed before
the formation of a photoresist. An anti-reflective coating
composition used for the anti-reflective coating is not limited to
a particular one, and may be appropriately selected from various
anti-reflective coating compositions that have been commonly used
for lithography process. Furthermore, the anti-reflective coating
may be formed using a common method, for example, application with
a spinner or a coater and baking.
The substrate to which the resist underlayer film-forming
composition of the present invention is applied may have an organic
or inorganic anti-reflective coating formed thereon by a CVD
process or the like, and furthermore, on the anti-reflective
coating, a resist underlayer film formed from the resist underlayer
film-forming composition of the present invention may be
formed.
In the present invention, the resist underlayer film functions as a
hard mask. In any developing process in any generation lithography,
the acidity of an underlayer film needs to be adjusted for the
purpose of controlling the shape of a resist. In particular, the
skeleton of the hydrolyzable silane that is incorporated into the
composition of the present invention so as to generate an acid by
the irradiation of lasers and electron beams with various
wavelengths, such as KrF, ArF, EUV, and EB, can contribute to a
higher contrast of a photoresist, and is therefore useful. In
particular, when the composition has a trifluoromethanesulfone
skeleton, an acid and a base can be characteristically generated
particularly in EUV exposure, and thus, pattern resolution can be
improved.
Sometimes, depending on the wavelength of light used in a
lithography process, the resist underlayer film formed from the
resist underlayer film-forming composition of the present invention
absorbs the light. In this case, the resist underlayer film can
function as an anti-reflective coating having the effect of
preventing light reflected from a substrate. Furthermore, the
underlayer film formed from the resist underlayer film-forming
composition of the present invention can be used as, for example, a
layer for preventing the interaction between a substrate and a
photoresist; a layer having the function of preventing a material
used for a photoresist or a substance produced at the time of
exposing a photoresist to light from having an adverse effect on a
substrate; a layer having the function of preventing a substance
produced in a substrate at the time of heating and baking from
diffusing to a photoresist serving as an upper layer; and a barrier
layer for reducing the effect of poisoning a photoresist layer by a
dielectric layer on a semiconductor substrate; or the like.
Furthermore, the resist underlayer film not only can function as a
hard mask, but can also be used as an EUV resist underlayer film
for the purpose below. That is, the resist underlayer film-forming
composition can be used for an anti-reflective EUV resist
underlayer coating that is capable of, without intermixing with an
EUV resist, preventing exposure light undesirable for EUV exposure
(wavelength of 13.5 nm), such as above-mentioned UV and DUV (ArF
laser, KrF laser), from reflecting from a substrate or an
interface. The reflection can be efficiently prevented in the
underlayer of the EUV resist. In the case where the resist
underlayer film is used as an EUV resist underlayer film, the film
can be processed in the same manner as for the underlayer film for
photoresists.
Furthermore, the resist underlayer film formed from the resist
underlayer film-forming composition of the present invention can be
applied to a substrate having via holes formed therein for use in
the dual-damascene process, and can be used as an embedding
material to fill up the holes. Furthermore, the resist underlayer
film can be used as a flattening material to make the surface of a
semiconductor substrate having projections and depressions
flat.
EXAMPLES
Synthesis of Compound
1/trifluoromethanesulfonylpropyltriethoxysilane
Into a 500-ml short-neck flask, 28.00 g (0.116 mol) of
3-chloropropyltriethoxysilane, 23.59 g (0.152 mol) of sodium
trifluoromethanesulfinate, 8.59 g (0.023 mol) of tetrabutylammonium
iodide (TBAI), 84.00 g of toluene, and 28.00 g of
N-methylpyrrolidone (NMP) were introduced, and heated to
100.degree. C. to effect the reaction for 24 hours. The resultant
reaction solution was subjected to liquid separation using toluene
and water, and then, toluene was removed by an evaporator to obtain
a crude product. The crude product was subjected to distillation
under reduced pressure to obtain a target, Compound 1
(trifluoromethanesulfonylpropyltriethoxysilane).
##STR00024##
.sup.1H-NMR (500 MHz, DMSO-d.sub.6): 0.78 ppm (m, 2H), 1.16 ppm (t,
9H), 1.84 ppm (m, 2H), 3.78 ppm (m, 8H) 13C-NMR (500 MHz,
DMSO-d.sub.6): 8.6 ppm, 15.3 ppm, 18.1 ppm, 50.6 ppm, 57.9 ppm,
119.2 ppm (q)
Synthesis of Compound 2/methanesulfonylpropyltriethoxysilane
Into a 500-ml short-neck flask, 50.00 g (0.208 mol) of
3-chloropropyltriethoxysilane, 22.26 g (0.218 mol) of sodium
methanesulfinate, 6.22 g (0.042 mol) of sodium iodide, and 200.00 g
of N-methylpyrrolidone were introduced, and heated to 150.degree.
C. to effect the reaction for 7 hours. The resultant reaction
solution was subjected to liquid separation using toluene and
water, and then, toluene was removed by an evaporator to obtain a
crude product. The crude product was subjected to distillation
under reduced pressure to obtain a target, Compound 2
(methanesulfonylpropyltriethoxysilane).
.sup.1H-NMR (500 MHz, DMSO-d.sub.6): 0.70 ppm (m, 2H), 1.16 ppm (t,
9H), 1.74 ppm (m, 2H), 2.93 ppm (s, 3H), 3.11 ppm (m, 2H), 3.76 ppm
(m, 6H)
Synthesis of Compound
3/trifluoromethanesulfonamidepropyltriethoxysilane
##STR00025##
Into a 200-ml four-neck flask, 15.00 g (0.068 mol) of
3-aminopropyltriethoxysilane, 7.20 g (0.071 mol) of triethylamine
(TEA), and 60 g of acetonitrile (MeCN) were introduced, and stirred
at 5.degree. C. 11.42 g (0.068 mol) of trifluoromethanesulfonyl
chloride was added dropwise to the resultant reaction mixture, and
then heated to 25.degree. C. and stirred for 3 hours. The resultant
salt was filtered off, followed by distillation under reduced
pressure to obtain a target,
trifluoromethanesulfonamidepropyltriethoxysilane.
.sup.1H-NMR (500 MHz, DMSO-d.sub.6): 0.58 ppm (t, 2H), 1.15 ppm (t,
9H), 1.53 ppm (m, 2H), 3.11 ppm (d, 2H), 3.75 (q, 6H), 9.32 (s,
1H)
Synthesis Example 1
24.82 g (70 mol %) of tetraethoxysilane, 1.69 g (5 mol %) of
phenyltrimethoxysilane, 6.07 g (20 mol %) of methyltriethoxysilane,
2.89 g (5 mol %) of trifluoromethanesulfonylpropyltriethoxysilane,
and 53.19 g of acetone were introduced into a 300-ml flask, and,
while the resultant mixed solution was stirred with a magnetic
stirrer, 11.35 g of 0.01 mol/l hydrochloric acid was added dropwise
to the mixed solution. After the completion of the addition, the
flask was transferred into an oil bath adjusted to 85.degree. C.,
and while being heated to reflux, the reaction was effected for 240
minutes. Then, the reaction solution was cooled down to room
temperature, and to the reaction solution, 70.00 g of propylene
glycol monomethyl ether acetate was added, and methanol and ethanol
as reaction by-products, acetone, water, and hydrochloric acid were
distilled off under reduced pressure, and the resultant reaction
mixture was concentrated to obtain a hydrolysis-condensation
product (polymer) propylene glycol monomethyl ether acetate
solution. To the obtained solution, propylene glycol monoethyl
ether was added to adjust the resultant solution so as to contain
solid residues of 20% by weight at 140.degree. C. with a solvent
ratio of propylene glycol monomethyl ether acetate/propylene glycol
monoethyl ether 20/80. The obtained polymer corresponded to Formula
(3-1) and had a weight average molecular weight of Mw 1,800 by GPC
in terms of polystyrene.
Synthesis Example 2
25.91 g (70 mol %) of tetraethoxysilane, 6.34 g (20 mol %) of
methyltriethoxysilane, 3.00 g (5 mol %) of
trifluoromethanesulfonylpropyltriethoxysilane, 2.15 g (5 mol %) of
4-methoxybenzyltrimethoxysilane, and 52.89 g of acetone were
introduced into a 300-ml flask, and, while the resultant mixed
solution was stirred with a magnetic stirrer, 11.85 g of 0.01 mol/l
hydrochloric acid was added dropwise to the mixed solution. After
the completion of the addition, the flask was transferred into an
oil bath adjusted to 85.degree. C., and while being heated to
reflux, the reaction was effected for 240 minutes. Then, the
reaction solution was cooled down to room temperature, and to the
reaction solution, 70.00 g of propylene glycol monomethyl ether
acetate was added, and methanol and ethanol as reaction
by-products, acetone, water, and hydrochloric acid were distilled
off under reduced pressure, and the resultant reaction mixture was
concentrated to obtain a hydrolysis-condensation product (polymer)
propylene glycol monomethyl ether acetate solution. To the obtained
solution, propylene glycol monoethyl ether was added to adjust the
resultant solution so as to contain solid residues of 20% by weight
at 140.degree. C. with a solvent ratio of propylene glycol
monomethyl ether acetate/propylene glycol monoethyl ether 20/80.
The obtained polymer corresponded to Formula (3-2) and had a weight
average molecular weight of Mw 1,600 by GPC in terms of
polystyrene.
Synthesis Example 3
24.32 g (70 mol %) of tetraethoxysilane, 1.65 g (5 mol %) of
phenyltrimethoxysilane, 3.87 g (13 mol %) of methyltriethoxysilane,
2.82 g (5 mol %) of trifluoromethanesulfonylpropyltriethoxysilane,
0.81 g (2 mol %) of 4-methoxybenzyltrimethoxysilane, 2.89 g (5 mol
%) of phenylslufonylpropyltriethoxysilane, and 53.33 g of acetone
were introduced into a 300-ml flask, and, while the resultant mixed
solution was stirred with a magnetic stirrer, 11.12 g of 0.01 mol/l
hydrochloric acid was added dropwise to the mixed solution. After
the completion of the addition, the flask was transferred into an
oil bath adjusted to 85.degree. C., and while being heated to
reflux, the reaction was effected for 240 minutes. Then, the
reaction solution was cooled down to room temperature, and to the
reaction solution, 70.00 g of propylene glycol monomethyl ether
acetate was added, and methanol and ethanol as reaction
by-products, acetone, water, and hydrochloric acid were distilled
off under reduced pressure, and the resultant reaction mixture was
concentrated to obtain a hydrolysis-condensation product (polymer)
propylene glycol monomethyl ether acetate solution. To the obtained
solution, propylene glycol monoethyl ether was added to adjust the
resultant solution so as to contain solid residues of 20% by weight
at 140.degree. C. with a solvent ratio of propylene glycol
monomethyl ether acetate/propylene glycol monoethyl ether 20/80.
The obtained polymer corresponded to Formula (3-3) and had a weight
average molecular weight of Mw 1,800 by GPC in terms of
polystyrene.
Synthesis Example 4
23.42 g (70 mol %) of tetraethoxysilane, 1.59 g (5 mol %) of
phenyltrimethoxysilane, 2.29 g (8 mol %) of methyltriethoxysilane,
2.71 g (5 mol %) of trifluoromethanesulfonylpropyltriethoxysilane,
0.77 g (2 mol %) of 4-methoxybenzyltrimethoxysilane, 2.78 g (5 mol
%) of phenylslufonylpropyltriethoxysilane, 2.91 g (5 mol %) of
2,2,2,5-trimethyl-5-(3-(triethoxysilyl)propyl)-1,3-dioxane-4,6-dione,
and 53.57 g of acetone were introduced into a 300-ml flask, and,
while the resultant mixed solution was stirred with a magnetic
stirrer, 10.71 g of 0.01 mol/l hydrochloric acid was added dropwise
to the mixed solution. After the completion of the addition, the
flask was transferred into an oil bath adjusted to 85.degree. C.,
and while being heated to reflux, the reaction was effected for 240
minutes. Then, the reaction solution was cooled down to room
temperature, and to the reaction solution, 70.00 g of propylene
glycol monomethyl ether acetate was added, and methanol and ethanol
as reaction by-products, acetone, water, and hydrochloric acid were
distilled off under reduced pressure, and the resultant reaction
mixture was concentrated to obtain a hydrolysis-condensation
product (polymer) propylene glycol monomethyl ether acetate
solution. To the obtained solution, propylene glycol monoethyl
ether was added to adjust the resultant solution so as to contain
solid residues of 20% by weight at 140.degree. C. with a solvent
ratio of propylene glycol monomethyl ether acetate/propylene glycol
monoethyl ether 20/80. The obtained polymer corresponded to Formula
(3-4) and had a weight average molecular weight of Mw 1,700 by GPC
in terms of polystyrene.
Synthesis Example 5
23.11 g (70 mol %) of tetraethoxysilane, 1.57 g (5 mol %) of
phenyltrimethoxysilane, 2.79 g (8 mol %) of
acetoxymethyltriethoxysilane, 2.68 g (5 mol %) of
trifluoromethanesulfonylpropyltriethoxysilane, 0.77 g (2 mol %) of
4-methoxybenzyltrimethoxysilane, 2.75 g (5 mol %) of
phenylslufonylpropyltriethoxysilane, 2.87 g (5 mol %) of
2,2,2,5-trimethyl-5-(3-(triethoxysilyl)propyl)-1,3-dioxane-4,6-dione,
and 53.66 g of acetone were introduced into a 300-ml flask, and,
while the resultant mixed solution was stirred with a magnetic
stirrer, 10.57 g of 0.01 mol/l hydrochloric acid was added dropwise
to the mixed solution. After the completion of the addition, the
flask was transferred into an oil bath adjusted to 85.degree. C.,
and while being heated to reflux, the reaction was effected for 240
minutes. Then, the reaction solution was cooled down to room
temperature, and to the reaction solution, 70.00 g of propylene
glycol monomethyl ether acetate was added, and methanol and ethanol
as reaction by-products, acetone, water, and hydrochloric acid were
distilled off under reduced pressure, and the resultant reaction
mixture was concentrated to obtain a hydrolysis-condensation
product (polymer) propylene glycol monomethyl ether acetate
solution. To the obtained solution, propylene glycol monoethyl
ether was added to adjust the resultant solution so as to contain
solid residues of 20% by weight at 140.degree. C. with a solvent
ratio of propylene glycol monomethyl ether acetate/propylene glycol
monoethyl ether 20/80. The obtained polymer corresponded to Formula
(3-5) and had a weight average molecular weight of Mw 2,100 by GPC
in terms of polystyrene.
Synthesis Example 6
23.74 g (70 mol %) of tetraethoxysilane, 3.37 g (5 mol %) of
triethoxysilylpropyldiallyl isocyanurate, 5.80 g (20 mol %) of
methyltriethoxysilane, 2.75 g (5 mol %) of
trifluoromethanesulfonylpropyltriethoxysilane, and 53.66 g of
acetone were introduced into a 300-ml flask, and, while the
resultant mixed solution was stirred with a magnetic stirrer, 10.85
g of 0.01 mol/l hydrochloric acid was added dropwise to the mixed
solution. After the completion of the addition, the flask was
transferred into an oil bath adjusted to 85.degree. C., and while
being heated to reflux, the reaction was effected for 240 minutes.
Then, the reaction solution was cooled down to room temperature,
and to the reaction solution, 70.00 g of propylene glycol
monomethyl ether acetate was added, and methanol, ethanol as
reaction by-products, acetone, water, and hydrochloric acid were
distilled off under reduced pressure, and the resultant reaction
mixture was concentrated to obtain a hydrolysis-condensation
product (polymer) propylene glycol monomethyl ether acetate
solution. To the obtained solution, propylene glycol monoethyl
ether was added to adjust the resultant solution so as to contain
solid residues of 20% by weight at 140.degree. C. with a solvent
ratio of propylene glycol monomethyl ether acetate/propylene glycol
monoethyl ether 20/80. The obtained polymer corresponded to Formula
(3-6) and had a weight average molecular weight of Mw 1,800 by GPC
in terms of polystyrene.
Synthesis Example 7
24.63 g (70 mol %) of tetraethoxysilane, 1.67 g (5 mol %) of
phenyltrimethoxysilane, 5.72 g (19 mol %) of methyltriethoxysilane,
2.86 g (5 mol %) of trifluoromethanesulfonylpropyltriethoxysilane,
0.61 g (0.1 mol %) of benzenesulfonamidepropyltriethoxysilane, and
53.24 g of acetone were introduced into a 300-ml flask, and, while
the resultant mixed solution was stirred with a magnetic stirrer,
11.26 g of 0.01 mol/l hydrochloric acid was added dropwise to the
mixed solution. After the completion of the addition, the flask was
transferred into an oil bath adjusted to 85.degree. C., and while
being heated to reflux, the reaction was effected for 240 minutes.
Then, the reaction solution was cooled down to room temperature,
and to the reaction solution, 70.00 g of propylene glycol
monomethyl ether acetate was added, and methanol and ethanol
reaction by-products, acetone, water, and hydrochloric acid were
distilled off under reduced pressure, and the resultant reaction
mixture was concentrated to obtain a hydrolysis-condensation
product (polymer) propylene glycol monomethyl ether acetate
solution. To the obtained solution, propylene glycol monoethyl
ether was added to adjust the resultant solution so as to contain
solid residues of 20% by weight at 140.degree. C. with a solvent
ratio of propylene glycol monomethyl ether acetate/propylene glycol
monoethyl ether 20/80. The obtained polymer corresponded to Formula
(3-7) and had a weight average molecular weight of Mw 1,800 by GPC
in terms of polystyrene.
Synthesis Example 8
24.55 g (70 mol %) of tetraethoxysilane, 7.60 g (20 mol %) of
methyltriethoxysilane, 3.01 g (5 mol %) of
triethoxysilylpropyltrifluoromethanesulfonamide, and 53.18 g of
acetone were introduced into a 300-ml flask, and, while the
resultant mixed solution was stirred with a magnetic stirrer, 11.36
g of 1 mol/l hydrochloric acid was added dropwise to the mixed
solution. After the completion of the addition, the flask was
transferred into an oil bath adjusted to 85.degree. C., and while
being heated to reflux, the reaction was effected for 240 minutes.
Then, the reaction solution was cooled down to room temperature,
and to the reaction solution, 70.00 g of propylene glycol
monomethyl ether acetate was added, and methanol and ethanol as
reaction by-products, acetone, water, and hydrochloric acid were
distilled off under reduced pressure, and the resultant reaction
mixture was concentrated to obtain a hydrolysis-condensation
product (polymer) propylene glycol monomethyl ether acetate
solution. To the obtained solution, propylene glycol monoethyl
ether was added to adjust the resultant solution so as to contain
solid residues of 20% by weight at 140.degree. C. with a solvent
ratio of propylene glycol monomethyl ether acetate/propylene glycol
monoethyl ether 20/80. The obtained polymer corresponded to Formula
(3-8) and had a weight average molecular weight of Mw 1,800 by GPC
in terms of polystyrene.
Comparative Synthesis Example 1
25.81 g (70% by mole) of tetraethoxysilane, 9.47 g (30% by mole) of
methyltriethoxysilane, and 52.92 g of acetone were introduced into
a 300-ml flask, and, while the resultant mixed solution was stirred
with a magnetic stirrer, 11.80 g of 0.01 mol/l hydrochloric acid
was added dropwise to the mixed solution. After the completion of
the addition, the flask was transferred into an oil bath adjusted
to 85.degree. C., while being heated to reflux, the reaction was
effected for 240 minutes. Then, the reaction solution was cooled
down to room temperature, and to the reaction solution, 70.00 g of
propylene glycol monomethyl ether acetate was added, and methanol
and ethanol as reaction by-products, acetone, water, and
hydrochloric acid were distilled off under reduced pressure, and
the resultant reaction mixture was condensed to obtain a
hydrolysis-condensation product (polymer) propylene glycol
monomethyl ether acetate solution. To the obtained solution,
propylene glycol monoethyl ether was added to adjust the resultant
solution so as to contain solid residues of 20% by weight at
140.degree. C. with a solvent ratio of propylene glycol monomethyl
ether acetate/propylene glycol monoethyl ether 20/80. The obtained
polymer corresponded to Formula (4-1) and had a weight average
molecular weight of Mw 1,700 by GPC in terms of polystyrene.
##STR00026##
Comparative Synthesis Example 2
25.21 g (70% by mole) of tetraethoxysilane, 7.71 g (25% by mole) of
methyltriethoxysilane, 2.45 g of
methanesulfonylpropyltriethoxysilane, and 53.08 g of acetone were
introduced into a 300-ml flask, and, while the resultant mixed
solution was stirred with a magnetic stirrer, 11.53 g of 0.01 mol/l
hydrochloric acid was added dropwise to the mixed solution. After
the completion of the addition, the flask was transferred into an
oil bath adjusted to 85.degree. C., while being heated to reflux,
the reaction was effected for 240 minutes. Then, the reaction
solution was cooled down to room temperature, and to the reaction
solution, 70.00 g of propylene glycol monomethyl ether acetate was
added, and methanol and ethanol as reaction by-products, acetone,
water, and hydrochloric acid were distilled off under reduced
pressure, and the resultant reaction mixture was condensed to
obtain a hydrolysis-condensation product (polymer) propylene glycol
monomethyl ether acetate solution. To the obtained solution,
propylene glycol monoethyl ether was added to adjust the resultant
solution so as to contain solid residues of 20% by weight at
140.degree. C. with a solvent ratio of propylene glycol monomethyl
ether acetate/propylene glycol monoethyl ether 20/80. The obtained
polymer corresponded to Formula (4-2) and had a weight average
molecular weight of Mw 1,800 by GPC in terms of polystyrene.
##STR00027##
Comparative Synthesis Example 3
23.22 g (70% by mole) of tetraethoxysilane, 5.68 g (20% by mole) of
methyltriethoxysilane, 6.85 g of
trifluoromethylsulfonylphenoxypropyltriethoxysilane, and 53.63 g of
acetone were introduced into a 300-ml flask, and, while the
resultant mixed solution was stirred with a magnetic stirrer, 10.62
g of 0.01 mol/l hydrochloric acid was added dropwise to the mixed
solution. After the completion of the addition, the flask was
transferred into an oil bath adjusted to 85.degree. C., while being
heated to reflux, the reaction was effected for 240 minutes. Then,
the reaction solution was cooled down to room temperature, and to
the reaction solution, 70.00 g of propylene glycol monomethyl ether
acetate was added, and methanol and ethanol as reaction
by-products, acetone, water, and hydrochloric acid were distilled
off under reduced pressure, and the resultant reaction mixture was
condensed to obtain a hydrolysis-condensation product (polymer)
propylene glycol monomethyl ether acetate solution. To the obtained
solution, propylene glycol monoethyl ether was added to adjust the
resultant solution so as to contain solid residues of 20% by weight
at 140.degree. C. with a solvent ratio of propylene glycol
monomethyl ether acetate/propylene glycol monoethyl ether 20/80.
The obtained polymer corresponded to Formula (4-3) and had a weight
average molecular weight of Mw 1,800 by GPC in terms of
polystyrene.
##STR00028##
Preparation of Si-Containing Resist Underlayer Film-Forming
Composition
Each of the silicon-containing polymers obtained in Synthesis
Examples 1 to 8 and Comparative Synthesis Examples 1 to 3 was mixed
with an acid, a curing catalyst, an additive, a solvent, and water
in ratios shown in Table 1. The mixture was filtered with a
0.1-.mu.m fluororesin filter to prepare a solution of the resist
underlayer film-forming composition. The blending ratios of the
polymers in Table 1 indicate not the blending amounts of the
polymer solutions, but the blending amounts of the polymers
themselves.
In Table 1, maleic acid is abbreviated as MA;
benzyltriethylammonium chloride is abbreviated as BTEAC;
N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole is abbreviated as
IMIDTEOS; triphenylsulfonium nitrate is abbreviated as TPSNO3;
monotriphenylsulfonium maleate is abbreviated as TPSMA;
triphenylsulfonium trifluoroacetate is abbreviated as TPSTFA;
triphenylsulfonium chloride is abbreviated as TPSCl;
triphenylsulfonium camphorsulfonate is abbreviated as TPSCS;
triphenylsulfonium trifluoromethanesulfonate is abbreviated as
TPSTf; triphenylsulfonium nonafluorobutanesulfonate is abbreviated
as TPSNf; triphenylsulfonium
adamantanecarboxy-1,1,2-trifluorobutanesulfonate is abbreviated as
TPSAdTF; dihydroxyphenylphenylsulfonium p-toluenesulfonate is
DHTPPSpTS; bisphenylsulfone is abbreviated as BPS; propylene glycol
monomethyl ether acetate is abbreviated as PGMEA; propylene glycol
monoethyl ether is abbreviated as PGEE; and propylene glycol
monomethyl ether is abbreviated as PGME. As the water, ultrapure
water was used. Each blending amount is expressed in part by
mass.
TABLE-US-00001 TABLE 1 Si polymer Acid Curing catalyst Additive
Solvent Example 1 Synthesis Example 1 MA TPSMA TPSCS PGME PGEE
PGMEA Water (part by mass) 2 0.02 0.06 0.1 15 65 5 15 Example 2
Synthesis Example 2 MA TPSNO3 TPSTf PGME PGEE PGMEA Water (part by
mass) 2 0.02 0.006 0.006 15 65 5 15 Example 3 Synthesis Example 3
MA BTEAC TPSNf PGME PGEE PGMEA Water (part by mass) 2 0.02 0.006
0.006 15 65 5 15 Example 4 Synthesis Example 4 MA IMIDTEOS PGME
PGEE PGMEA Water (part by mass) 2 0.02 0.006 15 65 5 15 Example 5
Synthesis Example 5 MA IMIDTEOS DHTPPSpTS PGME PGEE PGMEA Water
(part by mass) 2 0.02 0.006 0.006 15 65 5 15 Example 6 Synthesis
Example 6 MA TPSTFA TPSAdTF PGME PGEE PGMEA Water (part by mass) 2
0.02 0.06 0.1 15 65 5 15 Example 7 Synthesis Example 7 MA TPSC1 BPS
PGME PGEE PGMEA Water (part by mass) 2 0.02 0.006 0.1 15 65 5 15
Example 8 Synthesis Example 8 MA TPSNO3 TPSAdTF PGME PGEE PGMEA
Water (part by mass) 2 0.02 0.006 0.1 15 65 5 15 Comparative
Comparative MA TPSMA TPSCS PGME PGEE PGMEA Water Example 1
Synthesis Example 1 (part by mass) 2 0.02 0.06 0.1 15 65 5 15
Comparative Comparative MA TPSN03 TPSCS PGME PGEE PGMEA Water
Example 2 Synthesis Example 2 (part by mass) 2 0.02 0.06 0.1 15 65
5 15 Comparative Comparative MA TPSN03 TPSCS PGME PGEE PGMEA Water
Example 3 Synthesis Example 3 (part by mass) 2 0.02 0.06 0.1 15 65
5 15
Preparation of Organic Resist Underlayer Film-Forming
Composition
Under an atmosphere of nitrogen, carbazole (6.69 g, 0.040 mol,
manufactured by Tokyo Chemical Industry Co., Ltd.), 9-fluorenone
(7.28 g, 0.040 mol, manufactured by Tokyo Chemical Industry Co.,
Ltd.), and p-toluenesulfonic acid monohydrate (0.76 g, 0.0040 mol,
manufactured by Tokyo Chemical Industry Co., Ltd.) were introduced
into a 100-ml four-neck flask, and 1,4-dioxane (6.69 g,
manufactured by KANTO CHEMICAL CO., INC.) was charged therein and
stirred. The resultant mixture was dissolved with the temperature
increased to 100.degree. C. to initiate polymerization. After 24
hours, the product was left cool to 60.degree. C., and then,
chloroform (34 g, manufactured by KANTO CHEMICAL CO., INC.) was
added to dilute the product, and the resultant product was
reprecipitated in methanol (168 g, manufactured by KANTO CHEMICAL
CO., INC.). The obtained precipitate was filtered and dried with a
vacuum drier at 80.degree. C. for 24 hours, to obtain 9.37 g of a
polymer (Formula (5-1), hereinafter abbreviated as PCzFL) as a
target product.
##STR00029##
The measurement results of .sup.1H-NMR of PCzFL were as
follows.
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): 67.03-7.55 (br, 12H),
67.61-8.10 (br, 4H), .delta. 11.18 (br, 1H)
The weight average molecular weight Mw of PCzFL measured by GPC in
terms of polystyrene was 2,800, and the degree of poly-distribution
Mw/Mn was 1.77.
20 g of the obtained resin was mixed with 3.0 g of
tetramethoxymethyl glycoluril (the trade name Powderlink 1174,
manufactured by Mitsui Cytec Ltd.) as a crosslinking agent, 0.30 g
of pyridinium p-toluenesulfonate as a catalyst, and 0.06 g of
MEGAFAC R-30 (the trade name, manufactured by DIC Corporation) as a
surfactant. The mixture was dissolved in 88 g of propylene glycol
monomethyl ether acetate to form a solution. The solution was then
filtered with a polyethylene microfilter having a pore size of 0.10
.mu.m, and further filtered with a polyethylene microfilter having
a pore size of 0.05 .mu.m to prepare a solution of an organic
resist underlayer film (Layer A) forming composition used for a
lithography process using a multilayer film.
(Optical Constant Measurement)
Each of the Si-containing resist underlayer film-forming
compositions prepared in Examples 1 to 8 and Comparative Examples 1
to 3 was applied onto a silicon wafer by a spinner. The applied
compositions each were heated on a hot plate at 200.degree. C. for
1 minute to form the respective Si-containing resist underlayer
films (with a film thickness of 0.05 .mu.m). Then, the refractive
indexes (n value) and the optical absorption coefficients (also
referred to as k value or attenuation coefficient) at wavelengths
of 193 nm of these resist underlayer films were measured using a
spectroscopic ellipsometer (VUV-VASEVU-302, manufactured by J.A.
Woollam Co.).
(Measurement of Dry Etching Rate)
For the measurement of dry etching rate, the following etcher and
etching gas were used.
ES401 (manufactured by NIPPON SCIENTIFIC Co., Ltd.): CF.sub.4
RIE-10NR (manufactured by SAMCO INC.): O.sub.2
Each solution of the Si-containing resist underlayer film-forming
compositions prepared in Examples 1 to 8 and Comparative Examples 1
to 3 was applied onto a silicon wafer using a spinner. The applied
solutions were heated on a hot plate at 240.degree. C. for 1 minute
to form Si-containing resist underlayer films (having a film
thickness of 0.08 .mu.m (for the measurement of the etching rate
using CF.sub.4 gas) having a film thickness of 0.05 .mu.m (for the
measurement of the etching rate using O.sub.2 gas)). Furthermore,
in the same manner, an organic underlayer film-forming composition
was applied onto a silicon wafer using a spinner to form a coating
film (having a film thickness of 0.20 .mu.m). Using CF.sub.4 gas or
O.sub.2 gas as an etching gas, the dry etching rate of the organic
underlayer films was measured, and compared with the dry etching
rates of the Si-containing resist underlayer films of Examples 1 to
8 and Comparative Examples 1 to 3. The dry etching rate using the
fluorine-based gas was expressed in (nm/min). Furthermore, the
ratio of the etching rates using the oxygen-based gas was
calculated using (dry etching rate of Si-containing resist
underlayer film)/(dry etching rate of organic underlayer film).
(Evaluation of Resist Patterning: Evaluation Through NTD Process of
Performing Development Using Organic Solvent)
The organic underlayer film (Layer A)-forming composition
containing the structure of Formula (5-1) above was applied onto a
silicon wafer, and the applied organic underlayer film was baked on
a hot plate at 240.degree. C. for 60 seconds to obtain an organic
underlayer film (Layer A) having a film thickness of 200 nm. Each
of the Si-containing resist underlayer film (Layer B)-forming
compositions obtained in Examples 1 to 8 and Comparative Examples 1
to 3 was applied onto Layer A, followed by baking on a hot plate at
240.degree. C. for 60 seconds to obtain a Si-containing resist
underlayer film (Layer B). The Si-containing resist underlayer
films (Layers B) had a film thickness of 30 nm.
Onto each of Layers B, a commercially available photoresist
solution (trade name: FAiRS-9521NT05, manufactured by FUJIFILM
Corporation) was applied by a spinner, and heated on a hot plate at
100.degree. C. for 1 minute to form a photoresist film (Layer C)
having a film thickness of 85 nm.
Using a scanner, NSR-S307E, manufactured by Nikon Corporation
(wavelength: 193 nm, NA, .sigma.: 0.85, 0.93/0.85), each of the
photoresist films was exposed through a mask that allows the
formation of a 0.060-.mu.m line and space (L/S)=1/2 dense line, in
which the line width and the width between the lines of the
photoresist were each 0.060 .mu.m after development, or through a
mask that allows the formation of a 0.058-m line and space
(L/S)=1/1 dense line, in which the line width and the width between
the lines of a photoresist were each 0.058 .mu.m after development.
Then, the photoresist film was baked on a hot plate at 100.degree.
C. for 60 seconds, and cooled down, then developed using butyl
acetate (a solvent developer) for 60 seconds to form a
negative-type pattern on the resist underlayer film (Layer B). In
the obtained photoresist pattern, if any large pattern peeling,
undercut, and line having a wider bottom (footing) were not
observed, the pattern was evaluated as Good.
Table 2 shows refractive indexes at 193 nm, optical absorption
coefficients, fluorine gas etching rates, oxygen-based gas
resistance, and the lithography evaluation results of the skirt
shapes of resists.
TABLE-US-00002 TABLE 2 Oxygen- based Fluorine- gas based resistance
gas vs. Optical etching organic Skirt Refractive absorption rate
underlayer shape index coefficient (nm/min) film of resist Example
1 1.65 0.14 24 0.02 Good Example 2 1.60 0.25 25 0.03 Good Example 3
1.70 0.35 26 0.04 Good Example 4 1.68 0.33 27 0.04 Good Example 5
1.68 0.33 27 0.04 Good Example 6 1.64 0.14 30 0.03 Good Example 7
1.64 0.18 24 0.02 Good Example 8 1.56 0.08 23 0.02 Good Comparative
1.55 0.01 22 0.03 Footing Example 1 Comparative 1.57 0.07 23 0.03
Footing Example 2 Comparative 1.64 0.09 23 0.03 Collapse Example
3
[Resist Pattern Formation by EUV Exposure]
The organic underlayer film (Layer A)-forming composition was
applied onto a silicon wafer, and the applied organic underlayer
film was baked on a hot plate at 215.degree. C. for 60 seconds to
obtain an organic underlayer film (Layer A) having a film thickness
of 90 nm. The organic underlayer film (Layer A) was spin-coated
with each of the resist underlayer film-forming composition
solutions prepared in Examples 1, and 6 to 8, and Comparative
Examples 1 to 3, and was heated at 215.degree. C. for 1 minute to
form a resist underlayer film (Layer B) (20 nm). The resist
underlayer as a hard mask was spin-coated with a resist solution
for EUV (a methacrylate resin-based resist) and heated to form an
EUV resist layer (Layer C). The EUV resist layer (Layer C) was
exposed to light using an EUV exposure apparatus (Micro Exposure
Tool, abbreviated as MET) under the conditions of NA=0.30,
.sigma.=0.36/0.93, Quadropole. After the light exposure, PEB was
conducted, and then, the EUV resist layer was cooled to room
temperature on a cooling plate, and developed, followed by a
rinsing treatment to form a resist pattern. Formation of a
line-and-space pattern of 26 nm was evaluated, and the shape of the
pattern was evaluated by observing the section of the pattern.
In Table 3, Good means a state in which a shape between the footing
shape and the undercut shape has no significant amount of residues
in a space portion; Collapse means an unfavorable state in which a
resist pattern has peeled off and collapsed; Bridge means an
unfavorable state in which the top portions or bottom portions of a
resist pattern are in contact with each other; and Poor resist
coating properties means an unfavorable film forming state in which
cissing is found after resist film forming.
TABLE-US-00003 TABLE 3 Pattern shape Example 1 Good Example 6 Good
Example 7 Good Example 8 Good Comparative Example 1 Bridge
Comparative Example 2 Bridge Comparative Example 3 Poor resist
coating properties
INDUSTRIAL APPLICABILITY
The resist underlayer film-forming composition of the present
invention can be applied to, for example, resist underlayer
film-forming compositions for ArF, KrF photoresists or the like;
resist underlayer film-forming compositions for EUV resists or the
like; upper layer film-forming compositions for EUV resists, resist
underlayer film-forming compositions for electron beam resists or
the like; upper layer film-forming compositions for electron beam
resists; and reverse material-forming compositions.
* * * * *